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50+ Essential Terms

Amazon Seller Glossary (A–Z)

New to Amazon selling or lost among acronyms like FBA, ASIN, and ACoS? This glossary collects the essential terms for selling on Amazon, from A to Z. Each entry is explained clearly (no unnecessary jargon) to help you quickly understand the key concepts.

Maintained by SellerMagnet’s Amazon experts · Updated regularly

A

ACoS (Advertising Cost of Sale)

📊 Metrics

Indicates the advertising cost relative to the sales generated. Calculated as: ad spend ÷ ad sales × 100. A lower ACoS means your PPC campaign is more efficient (you’re spending less relative to the sales generated). Example: a 20% ACoS means for every $20 spent on ads, you generated $100 in sales from those ads. Typical ACoS targets vary by strategy: brand awareness campaigns may tolerate 40%+, while profit-focused campaigns aim for 15–25%. Your break-even ACoS equals your profit margin before ad spend. Tracking ACoS alongside TACoS (Total ACoS, which includes organic sales) gives the full picture of advertising efficiency.

Arbitrage (Retail/Online Arbitrage)

💼 Business

A business model where the seller purchases products from other sources (retail stores, outlets, e-commerce sites) at discounted prices to resell them on Amazon at a higher price. The arbitrager leverages the price difference as profit. It's a common strategy for new sellers, but you need to carefully select products with high demand and sufficient margin. Compare with Wholesale and Private Label.

ASIN (Amazon Standard Identification Number)

Title Checker

The unique identifier code assigned by Amazon to every product in its catalog. Composed of 10 alphanumeric characters (e.g., B08N5WRWNW), the ASIN allows Amazon to track, catalog, and index products across all its marketplaces. You can find a product’s ASIN in the “Product Information” section of any Amazon listing or in the URL. For sellers, understanding ASINs is crucial for product research (checking competitors and pricing), creating new listings, and running PPC campaigns with ASIN targeting. Each Amazon marketplace (US, UK, DE) may assign different ASINs to the same product. Note: for books, the ASIN often matches the ISBN. See also FNSKU, EAN/UPC, and ASIN Lookup.

Amazon Prime

📦 Logistics

Amazon's subscription program offering customers fast shipping (usually 1-2 days) for free plus other benefits (like Prime Video). For sellers, Prime is relevant because products managed through FBA automatically become Prime-eligible, making them more attractive to millions of Prime members. Having the Prime badge can increase sales and improve your chances of winning the Buy Box.

API (Application Programming Interface)

💼 Business

In the Amazon context, APIs allow external software (like SellerMagnet or other tools) to communicate with the Amazon platform and exchange data. For example, the Amazon MWS/SP-API allows you to download orders, update prices or quantities automatically. In short, Amazon APIs are digital "bridges" that enable automation and integration between Amazon and third-party applications.

ASIN Lookup

An ASIN Lookup is the process of searching for a product on Amazon using its unique ASIN code. By entering the 10-character ASIN into Amazon’s search bar (or a specialized tool), you can instantly pull up the product detail page with pricing, BSR, seller count, reviews, and category data. ASIN Lookup tools also let you reverse-search: enter an EAN/UPC barcode to find the corresponding ASIN, or convert ASINs across different Amazon marketplaces (US, UK, DE, etc.). This is invaluable for product research, competitive analysis, and cross-marketplace selling. Use the SellerMagnet ASIN Converter for free cross-marketplace lookups.

B

Brand Registry

🛡️ Brand

Amazon’s brand registration program for trademark owners. By enrolling a registered trademark in Brand Registry, you gain access to advanced tools to protect your brand (e.g., report violations, remove unauthorized listings) and features like A+ Content, dedicated Amazon Store, and Amazon Vine. Essentially, it protects your brand from counterfeits and hijackers while enhancing your brand presence on Amazon. For enrollment requirements and steps, see Amazon Brand Registry.

Buy Box (Featured Offer)

The Buy Box is the prominent “Add to Cart / Buy Now” section on the Amazon product page. When multiple sellers offer the same product, Amazon’s algorithm selects one as the “Featured Offer” based on factors including competitive pricing, fulfillment method (Prime/FBA is favored), seller performance metrics, stock availability, and shipping speed. Winning the Buy Box is critical because it captures approximately 83% of all Amazon sales. A Repricer can help you optimize pricing to win and maintain the Buy Box consistently while protecting your margins.

BSR (Best Sellers Rank)

📊 Metrics

Indicates a product’s ranking in Amazon’s sales charts within a specific category. A BSR of #1 means that product is the best-seller in its category. BSR is updated hourly based on recent and historical sales velocity: the lower the number, the higher the relative sales volume. Each product can have multiple BSR values (one per category and subcategory it belongs to). Sellers monitor BSR to evaluate product performance, estimate market demand, and identify trending opportunities. A sudden drop in BSR (lower number) signals a sales spike. Tools like SellerMagnet Sourcer can help track BSR trends over time and estimate monthly sales from BSR rankings.

C

Cross-Selling

💼 Business

A sales technique that involves offering the customer related or complementary products to what they're buying. On Amazon, cross-selling happens through sections like "Frequently Bought Together" or "Customers who bought this also bought…". For a seller, effective cross-selling means increasing the average cart value by offering relevant additional products. Optimizing your listings can help boost cross-sell opportunities.

Conversion Rate

📊 Metrics

In the Amazon context, indicates the percentage of product page visitors who actually make a purchase. For example, if 100 people visit your product page and 10 buy, the conversion rate is 10%. It's a key indicator of listing performance: a high conversion rate suggests that the title, images, price, and reviews are convincing customers. Optimizing page content and pricing can improve this metric, see Amazon SEO.

D

Dropshipping

💼 Business

A sales model where the seller doesn't physically hold inventory, but transfers customer orders directly to the supplier/manufacturer, who ships the product to the end buyer. On Amazon, dropshipping is only allowed if it complies with policies (for example, the package must not contain invoices or references to the external supplier, and the seller remains responsible for customer service). This model reduces initial inventory investment but may result in less control over quality and shipping times. Compare with FBA and FBM.

DSP (Demand-Side Platform)

💰 Advertising

Amazon's advertising platform that allows sellers and brands to purchase display and video ad space both on Amazon and on external websites/apps (through Amazon Advertising). Amazon DSP enables advanced retargeting and brand awareness campaigns, reaching a targeted audience using Amazon's data. It's a tool used primarily by sellers with larger advertising budgets or brands looking to increase visibility beyond standard PPC sponsorships like Sponsored Products.

E

EAN/UPC (Barcodes)

EAN (European Article Number) and UPC (Universal Product Code) are unique barcodes used to identify products globally. Amazon generally requires an EAN/UPC code to create a new product listing (unless you have a GTIN exemption or use an existing ASIN). Essentially, the EAN/UPC is the product's "ID number": for example, a book will have an ISBN, while a toy will have an EAN/UPC. Make sure to purchase valid codes (often through GS1) to avoid catalog errors.

F

FBA (Fulfillment by Amazon)

Amazon’s logistics service where Amazon handles storage, packing, shipping to customers, and post-sale support. The seller sends their inventory to Amazon warehouses (fulfillment centers) and delegates order management to them. FBA products automatically get the Prime badge and have better chances of winning the Buy Box thanks to fast, reliable shipping. Key FBA fees include a per-unit fulfillment fee (based on size and weight) and monthly storage fees (higher in Q4). Before sending any product, use the FBA Calculator to estimate profitability. For official fee schedules and guidelines, see Amazon Seller Central FBA Help. See also FNSKU, IPI, and Pan-European FBA.

FBA Calculator

An FBA Calculator is an essential tool that estimates your net profit per unit by factoring in Amazon’s FBA fees, referral fees, storage costs, shipping to the warehouse, and your product cost. The formula is straightforward: Net Profit = Sale Price − Product Cost − FBA Fee − Referral Fee − Storage Fee. For example, selling a product at $25 with a $6 product cost, $5.40 FBA fee, $3.75 referral fee, and $0.50 storage fee gives you a $9.35 net profit per unit (37.4% margin). Use the free SellerMagnet FBA Calculator to run these numbers before sourcing any product. See also ROI and Profit Calculator.

FBM (Fulfillment by Merchant)

A fulfillment method where the seller ships products directly to the customer (also called “Merchant Fulfilled”). With FBM, when an order comes in on Amazon, the seller handles packing, shipping, and customer service themselves. Advantages: full control over stock and shipments, no FBA storage/fulfillment fees, ideal for bulky, fragile, or slow-moving products, and the ability to include branded packaging. Disadvantages: no Prime badge by default (unless participating in Seller Fulfilled Prime), less appeal to Prime customers, and full responsibility for delivery timing and quality. Many sellers use a hybrid approach: FBA for fast-moving products and FBM for oversized or low-volume items. Compare your costs using the FBA Calculator.

FNSKU (Fulfillment Network SKU)

📦 Logistics

The identifier code used by Amazon to track products in its FBA fulfillment centers. Each unit you send to Amazon must have an FNSKU label so Amazon knows which seller it belongs to. The FNSKU is linked to the ASIN but is seller-specific. In practice, if two sellers sell the same ASIN via FBA, they'll have different FNSKUs, ensuring that when a customer buys from your offer, Amazon ships a product from your stock.

Seller Feedback

Ratings that customers leave about the seller (not the product). It's a star rating and comment reflecting the purchase experience (e.g., shipping times, communication, description accuracy). A high average feedback (close to 5 stars) and a good number of feedback ratings help your reputation and are considered by Amazon in account performance and Buy Box eligibility. Not to be confused with product reviews: seller feedback is about the service offered by the seller, while reviews are about product quality.

H

Hijacker (Listing Hijacking)

🛡️ Brand

A term for an "intruder" on your Amazon product listing. It happens when another seller adds themselves as an offer on your ASIN (perhaps your branded product) without authorization, often selling a counterfeit or parallel version at a lower price. Hijackers particularly target brand owners: beyond stealing the Buy Box and sales, they can damage the product's image (if they sell poor copies that generate negative reviews). To protect yourself from hijackers, it's advisable to enroll your trademark in Brand Registry, monitor your listings, and report violations to Amazon.

I

IPI (Inventory Performance Index)

📊 Metrics

The inventory performance index for FBA sellers, calculated by Amazon on a scale of 0-1000. It reflects how efficiently you manage stock in Amazon warehouses. Various factors influence IPI, including: sales rate relative to stock (sell-through), out-of-stock or excess inventory, stock without active offers, etc. A high IPI (e.g., 500+) indicates you're managing FBA inventory well (few stock-outs, little stagnant inventory), while a low IPI can lead to storage space restrictions. Keeping IPI above the minimum threshold (set by Amazon periodically, e.g., 400) is important to avoid FBA limitations.

ISBN (International Standard Book Number)

A 13-digit code used as a unique identifier for books. On Amazon, a book's ISBN often serves as the product code (ASIN) for that publication. If you sell books, you'll know the ISBN as it's used to search for and add titles to the catalog. For sellers, it's essentially the "publishing equivalent" of the EAN/UPC.

K

A key term used for searches on Amazon. When a customer types a word or phrase in the search bar (e.g., "Italian coffee maker 3 cups"), the system compares these keywords with those present in titles, bullet points, descriptions, and backend keywords of product listings. Optimizing your listings with the most relevant keywords means improving your Amazon SEO (visibility in internal search results). Additionally, keywords are the foundation of PPC advertising campaigns: by choosing the right keywords, you can reach the right audience in your Sponsored Products.

L

The Amazon page dedicated to a product, containing title, images, description, bullet points, technical details, and reviews. Creating an excellent listing is fundamental for selling: a clear title rich in keywords, professional photos, bullet points highlighting benefits, and an accurate description increase customer appeal and improve conversion rates. Listing quality also affects ranking in Amazon searches. Optimizing listings is part of Amazon SEO strategies. Use the free Title Checker to validate your listing title against 22 compliance rules.

M

MWS (Marketplace Web Service)

💼 Business

This was the name of Amazon's API platform for sellers (now largely replaced by the new SP-API). Amazon MWS allowed software and developers to interact with your account data (orders, inventory, reports) programmatically. For example, an order management tool could connect via MWS to automatically download orders and update availability. Although today we more often speak of Selling Partner API, many services and documentation still reference MWS.

N

Niche (Market Niche)

A specific, narrow market segment that a product focuses on. Finding a profitable niche is the secret of many successful sellers: it means identifying a particular need of a defined audience (example: "eco-friendly yoga accessories for travelers") and serving that market with a dedicated offering. On Amazon, working in niches can mean less competition and more targeted customers, but it's important to verify there's sufficient demand. Product research tools help discover niches by monitoring BSR trends, search volumes, and competition.

O

ODR (Order Defect Rate)

📊 Metrics

The percentage of defective orders for a seller, a key performance metric on Amazon. It includes three components: negative buyer feedback, A-to-Z claims, and chargebacks related to orders. Amazon requires sellers to maintain ODR below 1% to avoid penalties or account suspension. For example, out of 100 orders, fewer than 1 should have serious problems. To keep ODR low, you need to offer excellent service: accurate descriptions, timely shipping, proper packaging, and responsive customer support.

Lightning Deal

💰 Advertising

A time-limited promotion on Amazon where a product is offered at a significant discount for a limited period (usually a few hours). Lightning Deals appear in special showcases (e.g., Deal of the Day page) and can generate sales and visibility spikes. Sellers can propose Lightning Deals through Seller Central, but Amazon applies selection criteria (e.g., sales history, product rating) and often a participation fee. They're useful tools during events like Prime Day or Q4 Black Friday to boost sales.

P

PPC (Pay-Per-Click)

💰 Advertising

An online advertising model where the seller pays only when a user clicks on their ad. On Amazon, PPC includes three main campaign types: Sponsored Products (keyword and product-targeted ads in search results), Sponsored Brands (banner ads featuring your logo and multiple products), and Sponsored Display (retargeting ads on and off Amazon). You set bids per click and daily budgets to control spend. A well-optimized PPC campaign increases product visibility and sales, but needs constant monitoring to ensure the cost per click is sustainable relative to sales generated (see ACoS). Start with automatic targeting campaigns to discover high-performing keywords, then refine with manual campaigns.

Private Label

💼 Business

A business model where an Amazon seller creates and sells products under their own brand. Instead of reselling existing brands, in Private Label you identify a product (often through OEM suppliers), customize it with your own brand and packaging, and import it to sell as your own. Advantages: complete control over branding, less Buy Box competition (being the only seller of your brand), and potentially higher margins. However, it requires investment in product development, marketing, and quality, plus brand protection from imitations (where Brand Registry comes in handy).

Prime Day

💼 Business

Amazon's annual sales event, exclusive to Amazon Prime members. It consists of days (usually two) with thousands of special offers in July or summer, often compared in impact to Q4 Black Friday. For sellers, Prime Day represents a huge opportunity to increase sales thanks to the enormous traffic of Prime customers looking for deals. Many sellers prepare extra stock, dedicated advertising campaigns, and Lightning Deals well in advance.

Pan-European FBA Program

📦 Logistics

Amazon's logistics initiative for European sellers: it allows you to store inventory in one country but make products Prime-eligible across all EU marketplaces, with Amazon internally reallocating stock closer to customers. In practice, you ship products to a central warehouse (e.g., Germany) and Amazon distributes at no extra cost to other hubs across Europe based on demand. Pan-EU FBA simplifies international selling (no need to manually manage warehouses for each nation), but involves managing VAT aspects in multiple countries since stock is moved across borders.

Profit Calculator

A Profit Calculator helps Amazon sellers determine the true margin on every sale by accounting for all costs: product cost, FBA or FBM fulfillment fees, referral fees, advertising spend (ACoS), returns, and more. Unlike a basic fee calculator, a profit calculator provides an ongoing view of your Amazon business profitability. For example: $30 sale price with $8 total Amazon fees, $10 product cost, and $3 ad spend gives you $9 profit (30% margin). The SellerMagnet Profit Dashboard tracks all these variables in real time across your catalog. See also FBA Calculator and Revenue Calculator.

Q

Q4 (Fourth Quarter)

💼 Business

Refers to the fourth quarter of the year (October, November, December), a crucial period for e-commerce and Amazon sales. Q4 includes Black Friday, Cyber Monday, and the entire holiday shopping season. Many sellers record very high percentages of their annual revenue in these three months. Preparing for Q4 means ensuring sufficient stock, optimizing listings, increasing advertising budgets, and planning promotional offers, since consumer demand reaches its peak.

R

Reviews (Product Reviews)

Ratings and written opinions that customers leave on a product page after purchase. Product reviews (with star ratings) enormously influence buying decisions on Amazon: a product with many positive reviews will have higher conversions and may rank better in searches. Sellers must follow policies in review strategies (no incentives for positive reviews) and can use tools like Amazon's Request a Review or automated services to legitimately solicit customer feedback. See also Amazon Vine.

A-to-Z Claim

📊 Metrics

The protection Amazon offers buyers to ensure a refund when they're not satisfied with a Marketplace order. If a customer opens an A-to-Z Claim, Amazon evaluates the situation (product not received, different from description, defective, etc.) and may refund the buyer from the seller's funds if they deem the complaint valid. For the seller, an A-Z claim negatively impacts Order Defect Rate. Avoiding A-Z claims means providing accurate information, shipping on time, and promptly resolving any issues reported by customers.

Repricer (Repricing Tool)

Software that automatically adjusts your product prices on Amazon based on certain rules or algorithms. The main goal of a repricer is to keep prices competitive to win or maintain the Buy Box without manual intervention 24/7. Repricing strategies range from simple rule-based approaches (e.g., “match lowest price minus $0.01”) to advanced algorithms that consider competitor behavior, sales velocity, time of day, and stock levels. Key features to look for include minimum margin protection, multi-marketplace support, and speed of price updates. The faster updates happen, the more competitive you stay. Amazon offers a basic built-in tool (Automate Pricing), but advanced third-party solutions like SellerMagnet Repricer provide more sophisticated rule-based strategies and faster repricing cycles.

ROI (Return on Investment)

Return on investment, expressed as a percentage, calculated as: net profit ÷ investment cost × 100. In the Amazon context, ROI is often used to evaluate the profitability of a product or advertising campaign. For example, if you invest $10 total (product cost + shipping + fees) and earn $30 in sales with $20 net profit, your ROI is 200%. Experienced Amazon sellers typically target a minimum ROI of 100% (doubling their money) for arbitrage and 30–50% for private label. Always calculate ROI factoring ALL costs: product, shipping to Amazon, FBA fees, referral fees, advertising spend, and returns. The SellerMagnet Profit Dashboard calculates ROI automatically per product.

Revenue Calculator

An Amazon Revenue Calculator estimates total revenue and net earnings from your FBA or FBM sales by modeling different pricing and volume scenarios. The core formula: Monthly Revenue = Units Sold × Sale Price, and Net Revenue = Monthly Revenue − Total Fees − Total COGS. For example, selling 500 units/month at $25 generates $12,500 revenue; after $4,500 in fees and $3,000 COGS, your net revenue is $5,000 (40% net margin). Revenue calculators help sellers set realistic sales targets, plan inventory, and evaluate whether a product is worth scaling. The SellerMagnet Profit Dashboard provides real-time revenue tracking with all fees pre-calculated. See also ROI and Profit Calculator.

S

Amazon’s web platform through which Marketplace sellers manage their entire business. Through Amazon Seller Central you can add new products or offers, update prices and quantities, manage orders, set up advertising campaigns, monitor performance with reports and metrics, open support cases, and much more. Key sections include Inventory (manage your catalog), Orders (track fulfillment), Advertising (create and manage PPC campaigns), Reports (download business and payment reports), and Performance (track account health metrics like ODR). For official documentation, see Amazon Seller Central Help. Tools like SellerMagnet integrate via API to simplify and enhance these activities with more readable dashboards, repricing automation, and custom alerts.

SEO (Search Engine Optimization on Amazon)

On Amazon, refers to optimizing product pages to rank higher in internal search results. It works with principles similar to Google SEO but applied to the marketplace: you need to include relevant keywords in the title, bullets, and backend, use quality images, get good reviews, and maintain a good conversion rate. All these factors contribute to your product listing's relevance and performance in Amazon's A9/A10 search algorithm. Good Amazon SEO increases your products' organic visibility, reducing dependence on paid advertising.

Sponsored Products

💰 Advertising

A pay-per-click ad format on Amazon. Sponsored Products campaigns promote specific products and appear both in search results (at the top or middle of the list, with "Sponsored" label) and on product pages of other items. When a shopper clicks the ad, they're taken to your product page and you pay the click cost. These sponsorships are a key tool for giving your products visibility, especially during launches or in highly competitive categories, and work based on keywords or product/category targeting chosen in the campaign.

U

Ungating (Category/Product Approval)

💼 Business

The process of obtaining authorization to sell in product categories or brands initially blocked on Amazon. Some categories (e.g., Jewelry, Grocery) or brands require sellers to provide documentation (supplier invoices, licenses, certifications) to demonstrate reliability and compliance before they can create offers. This process is called ungating. If you want to expand your catalog into a restricted category, you must submit an approval request through Seller Central, attaching the required documents. Once approved, your account is "ungated" and you can freely sell those products.

V

Vendor Central

💼 Business

A platform reserved for Amazon suppliers (first-party sellers). Unlike Seller Central (for third-party marketplace sellers), Vendor Central is used by brands and distributors who sell their products directly to Amazon wholesale. Amazon becomes the final retailer, offering products as "Sold and shipped by Amazon." Vendors have a different relationship: they receive purchase orders from Amazon, manage wholesale pricing, and have access to specific marketing tools (like free Amazon Vine, extended Display campaigns, etc.). The transition to Vendor Central happens only by Amazon invitation.

Vine (Amazon Vine Program)

🛡️ Brand

An Amazon program (part of Brand Registry) that helps sellers get reviews on new products through a community of top reviewers. The Vine Program allows registered brands to offer a certain number of free units of a new product to "Vine Voices" (trusted reviewers selected by Amazon); in return, these users will try the product and publish an honest review. It's a legal and transparent way to break the "zero reviews" cycle when launching an item. Note: there's a cost to enroll an ASIN and a quantity limit, but a handful of initial quality reviews through Vine can boost product trust.

W

Wholesale (Wholesale Selling on Amazon)

A model where the seller purchases large quantities of products from official manufacturers or wholesalers to resell on Amazon (often on existing product pages, competing with other sellers). Doing wholesale means having B2B relationships with suppliers and often getting very low unit prices thanks to volume. It's the typical model for professional resellers: instead of hunting retail deals (arbitrage) or developing their own brand (private label), they choose established brands and resell them as authorized resellers. Important in this model is finding products with sufficient ROI, avoiding brands with too many resellers (Buy Box competition risk), and maintaining adequate stock levels.

Quick Comparison Tables

FBA vs FBM Quick Comparison

Feature FBA FBM
Shipping Amazon handles everything Seller ships directly
Prime Badge ✅ Automatic ❌ Only via SFP
Buy Box Advantage ✅ Strong preference ⚠️ Requires great metrics
Storage Fees Monthly + long-term fees Your own warehouse costs
Customer Service Amazon handles it Seller responsibility
Best For Fast-moving, small items Bulky, slow, or fragile items

Key Amazon Metrics at a Glance

Metric Formula Healthy Target
ACoS Ad Spend ÷ Ad Sales × 100 15–25% (profit-focused)
ROI Net Profit ÷ Cost × 100 100%+ (arbitrage), 30%+ (PL)
Conversion Rate Orders ÷ Sessions × 100 10–15% avg on Amazon
ODR Defective Orders ÷ Total Below 1% (mandatory)
IPI Amazon composite score 400+ (min), 500+ (ideal)
BSR Sales velocity ranking Lower = better sales

Amazon Business Models Compared

Aspect Private Label Wholesale Arbitrage
Startup Cost High ($2K–$10K+) Medium ($500–$5K) Low ($100–$500)
Margin 25–40% 10–20% 15–30%
Buy Box Competition None (your brand) Medium to High High
Scalability Very High High Limited
Brand Control Full None None
Best For Long-term brand building Steady, predictable sales Quick cash flow, learning

Frequently Asked Questions

The essential terms include ASIN (Amazon’s unique product identifier), FBA and FBM (the two fulfillment models), Buy Box (the featured offer that captures most sales), ACoS (advertising efficiency metric), and BSR (Best Sellers Rank). Mastering these concepts is the foundation for running a profitable Amazon business.

ASIN stands for Amazon Standard Identification Number. It is a unique 10-character alphanumeric code assigned to every product in Amazon’s catalog. ASINs are essential for product research, listing optimization, and tracking competitor activity. Every seller needs to understand ASINs to navigate the marketplace effectively.

With FBA (Fulfillment by Amazon), you send inventory to Amazon’s warehouses and they handle storage, packing, shipping, and customer service. With FBM (Fulfillment by Merchant), you manage the entire fulfillment process yourself. FBA products qualify for Prime and often win the Buy Box more easily, while FBM gives you more control over costs and logistics.

The Buy Box is the prominent “Add to Cart” section on a product page. When multiple sellers offer the same product, Amazon’s algorithm selects one as the featured offer based on factors like price, fulfillment method, seller metrics, and stock availability. Winning the Buy Box is critical because it captures the vast majority of sales on a listing.

ACoS (Advertising Cost of Sale) measures how much you spend on ads relative to the revenue those ads generate. It is calculated as ad spend ÷ ad sales × 100. A “good” ACoS depends on your margins and goals: brand awareness campaigns may tolerate 40%+, while profit-focused campaigns typically aim for 15%–25%. The lower the ACoS, the more efficient your advertising.

We regularly update this glossary to reflect new terms, policy changes, and evolving Amazon features. As Amazon introduces new programs, metrics, or seller tools, we add the relevant definitions so you always have an accurate and current reference.

An FBA Calculator estimates your net profit per unit by subtracting Amazon’s FBA fulfillment fee, referral fee, and storage costs from your sale price. Enter your product cost and desired sale price to see the estimated margin instantly. It is the first step before sourcing any product for Amazon FBA.

A repricer automatically adjusts your product prices based on rules or algorithms to help you win or maintain the Buy Box. It monitors competitor prices and updates yours in real time, ensuring you stay competitive without manual effort. Advanced repricers add minimum margin protection and customizable rule-based strategies.

BSR (Best Sellers Rank) indicates how well a product sells relative to others in the same category. A BSR of #1 means the product is the top seller. BSR is updated hourly based on recent and historical sales. Sellers use BSR to evaluate demand, compare products, and estimate monthly sales volume.

PPC (Pay-Per-Click) is Amazon’s internal advertising system where you only pay when someone clicks your ad. The three main formats are Sponsored Products (appear in search results), Sponsored Brands (banner ads with your logo), and Sponsored Display (retargeting on and off Amazon). PPC is essential for launching new products and boosting visibility.

ASIN Lookup is the process of searching for a product using its unique Amazon identifier. It lets you pull up pricing, BSR, review count, and seller data instantly. Reverse ASIN lookup tools also convert EAN/UPC barcodes to ASINs or find the same product across different Amazon marketplaces. It is a core step in product research.

ROI (Return on Investment) is calculated as net profit ÷ total investment cost × 100. For Amazon sellers, total cost includes product cost, shipping, FBA fees, referral fees, and advertising. For example, a $10 investment yielding $20 net profit equals a 200% ROI. Experienced arbitrage sellers target at least 100% ROI per product.

Amazon Brand Registry is a free program for trademark owners that unlocks brand protection tools, A+ Content, Amazon Stores, and Vine. Any seller with a registered trademark should enroll. It helps you report counterfeit listings, control your brand’s appearance, and access advanced marketing features.

ODR measures the percentage of orders with defects: negative feedback, A-to-Z claims, or chargebacks. Amazon requires ODR to stay below 1%. Exceeding this threshold can trigger warnings or account suspension. Keeping ODR low requires accurate listings, timely fulfillment, and responsive customer service.

Private Label means creating your own branded products for full control and higher margins. Wholesale involves buying branded products in bulk from manufacturers to resell. Arbitrage means finding discounted products in retail or online stores and reselling them on Amazon. Each model has different startup costs, margins, and scalability profiles.

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