Posted on September 2, 2025 · 16 min read

Seller Assistant API

Veronika Grishkova
Veronika Grishkova
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This guide will help you get started, understand the basics of Amazon selling, and explain in simple words how it all works.

If you’re an Amazon seller working through wholesale price lists, you know how challenging it can be to process all that essential product data efficiently. Whether you’re using tools like Airtable, Make, Zapier, Excel, Google Sheets, or custom software, the Seller Assistant API makes it easier to spot high-margin, low-risk deals.

By combining data from Keepa and Amazon SP API into one simple platform, it streamlines your workflow and saves you time. When researching new deals, the Seller Assistant API provides the insights you need to make smarter, faster decisions and grow your Amazon business.

This post tells what Seller Assistant API is and how it works.

Note. Seller Assistant is a comprehensive product-sourcing software that helps Amazon sellers quickly find high-profit deals. It combines three extensions: Seller Assistant Browser Extension, and IP-Alert Chrome Extension by Seller Assistant, and VPN by Seller Assistant, Amazon seller tools: Price List Analyzer, Brand Analyzer, Seller Spy, Bulk Restrictions Checker, and API integrations, and features: Storefront Widget,  Side Panel View, FBM&FBA Profit Calculator, Quick View, ASIN Grabber, UPC/EAN to ASIN converter, Stock Checker, IP Alert, and Restrictions Checker.

Seller Assistant

Seller Assistant

Seller Assistant shows all essential product data on Amazon search, product, and inventory pages, and on any website to help you find high-margin deals. By using this FBA and FBM product sourcing software, you can easily identify products that have the potential to be sold well on Amazon.

What Is Seller Assistant API?

Seller Assistant API is a comprehensive tool that helps Amazon sellers efficiently process essential product data and streamline their workflows. Designed for sellers who scan wholesale price lists or manage extensive product catalogs, this API simplifies tasks like profitability analysis, sales tracking, and product eligibility checks by integrating data from Keepa and Amazon SP API into a unified platform.

Seller Assistant API

Seller Assistant API

This tool empowers Amazon sellers to quickly evaluate products, detect high-margin, low-risk deals, and optimize their inventory decisions. With a single API key, sellers can easily access data across multiple sources, reducing time and effort spent on manual research and calculations.

Seller Assistant API is designed specifically for Amazon wholesale sellers scanning wholesale price lists for profitable deals and online arbitrage sellers and dropshippers processing bulk fetched supplier data. It helps efficiently scout for high-demand, low-competition products, facilitating reliable data-based portfolio expansions.

Seller Assistant API Functionality

Seller Assistant API provides actionable insights and automates data retrieval tasks, helping sellers efficiently evaluate potential deals and make data-driven decisions. By integrating seamlessly with tools like Airtable, Zapier, and Google Sheets, it fits into existing workflows with ease.

  • Identify products accurately

Match supplier catalog items to Amazon listings with ASINs, titles, brands, categories, UPC/EAN/GTIN identifiers, and manufacturer details — ensuring reliable product identification and correct mapping.

  • Estimate product performance

Use Best Sellers Rank (BSR) to measure demand, Top % BSR for sales velocity, monthly sales and revenue estimates for demand forecasting, and historical sales trends to predict future performance.

  • Calculate pricing and profitability

Compare supplier cost (COG), Buy Box price, and break-even thresholds; calculate ROI, profit per unit, and margins for both FBA and FBM; ensure each product sourced meets your profitability targets.

  • Break down Amazon fees and fulfillment costs

Access detailed costs including FBA/FBM fees, referral fees, storage, inbound shipping, labeling, prep, fragile packaging, and variable closing fees — helping you calculate true landed costs and profitability.

  • Detect restrictions and risks early

Instantly check if products are gated, require approval, or carry hidden risks such as HazMat, meltable, fragile, oversize, bundles, or IP complaints — avoiding compliance issues or unsellable inventory.

  • Understand dimensions and packaging impact

Review product size, weight, volume, and package quantity to estimate shipping costs, storage fees, and handling requirements for smarter inventory planning.

  • Analyze competition and pricing history

Track FBA and FBM seller counts, Buy Box share, and competitor offers; leverage Keepa-powered price history (30–365 days) to evaluate pricing stability and decide if listings are worth entering.

  • Automate data workflows

Convert ASINs to UPCs/EANs, refresh product data automatically, and integrate insights directly into Airtable, Zapier, Google Sheets, or custom systems — reducing manual work and speeding up analysis.

Seller Assistant API data

Product identification and details

  • ASIN

Amazon Standard Identification Number for the product

  • Link

Direct link to the product listing on Amazon

  • Title

Product name or title as it appears on Amazon

  • Brand

Manufacturer or brand of the product

  • Category

The product’s category on Amazon

  • Model, manufacturer, part number

Specific details related to the product’s manufacturing necessary to match the product to supplier catalog

Sales performance metrics

  • BSR (Best Sellers Rank)

Indicator of the product’s sales ranking within its category. Shows how well the product sells

  • Top BSR

Top helps understand the product’s sales velocity as a percentage. If the Top equals 0.5% or less, the product sells well. If the Top equals 1% or more, a product is a slow-mover

  • Sales Estimate (pcs/month)

Estimated number of units sold per month. Helps understand average product sales to estimate how many units to order

  • Sales Estimate ($/month)

Estimated revenue per month from product sales. Helps understand how much money you can potentially earn from product sales/month

Pricing and profitability

  • COG (Cost of Goods)

Cost of goods before tax. Product price at the supplier

  • Cost of Goods incl. VAT

Total cost including VAT

  • Buy Box price

Current price of the product winning the Buy Box on Amazon

  • Break-Even price (FBA/FBM)

The minimum product price with 0% profit for Fulfillment by Amazon (FBA) or Fulfillment by Merchant (FBM). If you go below break-even threshold, you lose money on the product

  • Profit (FBA/FBM)

Estimated profit per unit using FBA or FBM fulfillment methods. Shows how much money you earn on the product

  • ROI (FBA/FBM, %)

Return on investment for FBA or FBM orders, as a percentage

  • Margin (FBA/FBM, %)

Profit margin after costs, expressed as a percentage

Fulfillment costs

  • Total FBA/FBM fees

Overall fees associated with FBA or FBM services

  • FBA fees

Fulfillment by Amazon fees

  • Referral fee

Amazon’s percentage-based fee on the sale

  • Storage fees

Cost to store the product in Amazon’s warehouse

  • Variable Closing Fee

A fee applied for books, music, video, blu-ray, and DVDs (BMVD) on top of other fees

  • Inbound shipping costs (FBA)

Cost of shipping the product to an Amazon warehouse (for FBA)

  • Prepare/labeling cost (FBA/FBM)

Cost for preparing or labeling the product for shipment

  • Fragile/bubble wrapping (FBA/FBM)

Additional cost if the product requires special packaging for fragility

Product restrictions and flags

Product restrictions and flags

Product restrictions and flags

  • Warning

Shown if the product has any alerts, for example: no FBA Fees, no Buy Box price, no COGs, ASIN not found, set or bundle, approval required, too low FBA ROI, too high FBA ROI. For such products, more detailed research is required

  • Oversize flag

Marks if the product is considered oversize by Amazon

  • HazMat flag

Indicates if the product is classified as hazardous material

  • Meltable flag

Alerts for products that can melt in certain conditions

  • Fragile flag

Marks fragile products requiring special handling

  • IP complaints flag

Indicates the risk of intellectual property complaints

  • Variation flag

Denotes if the product has multiple variations (size, color, etc.)

  • Set/bundle flag

Marks if the product is part of a set or bundle

Dimensions and Packaging

  • Height, width, length, weight (in/cm/lbs/kg)

Physical dimensions and weight of the product, useful for calculating shipping costs

  • Product volume (cu ft/cu cm)

The product’s volume, helpful for storage and shipping calculations

  • Package quantity

Number of units in a package

Additional identifiers

  • UPC, EAN, GTIN

Global Trade Item Numbers used for identifying the product in various marketplaces

  • Parent ASIN

The parent ASIN, if the product has multiple variations

Benefits of Seller Assistant API

Seller Assistant API is your ultimate tool for simplifying Amazon product sourcing. By combining data from Keepa and Amazon SP API, it empowers sellers to access powerful insights and automate workflows for better efficiency. With just one API key, you can unlock essential information to make smarter, faster decisions.

Benefits of Seller Assistant API

Benefits of Seller Assistant API

Integrated data from Keepa and Amazon SP API

The Seller Assistant API merges the power of Keepa and Amazon SP API into a single platform. With Keepa, you can analyze product price history, Buy Box data, and product offers. Amazon SP API adds crucial details like inventory data, eligibility checks, and product performance metrics. Together, they provide a comprehensive view of every product you’re considering.

Comprehensive product data

Instantly access detailed product information, including ASINs, titles, categories, variations, and key product tags like heavy and bulky, meltable, fragile, or hazmat. This makes evaluating wholesale or arbitrage opportunities easier than ever.

Profitability calculations

Quickly calculate fees, profit margins, ROI, and break-even prices to ensure every product is a smart addition to your inventory.

Price history insights

Leverage data from Keepa to track average prices, Buy Box trends, and pricing dynamics over 30, 90, 180, and 365 days. Use these insights to identify profitable, low-risk opportunities.

Dynamic pricing metrics

Monitor price fluctuations caused by price wars or changing market trends. This helps you stay competitive and adjust your strategies accordingly.

Competition insights

Gain a clear picture of your competition by analyzing FBA and FBM offers, seller counts, and historical trends. This data lets you make better-informed decisions about pricing and product selection.

Sales performance metrics

Access BSR data, monthly sales estimates, and BSR drops across 30, 90, 180, or 365 day time frames. These insights help you understand product demand and sales potential.

Product restrictions and risk factors

Easily check product restrictions or eligibility to sell items on your Amazon account. Identify risk factors like whether a product is fragile, heavy and bulky, meltable, hazmat, or categorized as adult content. This helps estimate potential additional costs and make informed sourcing decisions.

Automated analysis

Save time by automating routine tasks like checking product restrictions or converting ASINs into UPCs and EANs (or backwards).

Pre-configured requests

Jumpstart your workflows with ready-to-use API endpoints for common tasks, reducing setup time and technical complexity.

Marketplace coverage

Operate across multiple Amazon marketplaces, including the US, UK, Canada, Europe, and more.

Seller Assistant API Use Cases

Seller Assistant API is an advanced tool designed to meet the needs of wholesale sellers scanning wholesale price lists for profitable deals and online arbitrage sellers and dropshippers processing bulk fetched supplier data. From product research to profitability analysis, it streamlines processes and provides actionable insights. Below are common use cases and how Seller Assistant API provides effective solutions.

Seller Assistant API Use Cases

Seller Assistant API Use Cases

Sellers need to quickly evaluate wholesale price lists

  • Use case

Sellers often have to process bulk wholesale price lists and identify profitable, low-risk products. This can be a time-consuming and tedious task.

  • Solution

Seller Assistant API automates the analysis of wholesale price lists by instantly fetching product data such as ASINs, titles, fees, and profitability calculations. Sellers can easily identify high-margin, low-risk products and save hours of manual research.

Sellers need to seamlessly connect their tools

  • Use case

Sellers often rely on tools like Airtable, Make, Zapier, Excel, Google Sheets, or custom software to manage their workflows. However, without proper integration, they waste time on repetitive tasks like matching ASINs with supplier UPCs or EANs, refreshing product data across marketplaces, or exporting competition and profitability data to share with their team.

  • Solution

Seller Assistant API bridges the gap between data and execution by integrating seamlessly with your existing tools. It automates tasks like syncing ASINs, updating product data, and exporting deal metrics, allowing sellers and their team to focus on strategy instead of manual processes.

Online arbitrage sellers and dropshippers need to process fetched supplier data

  • Use case

Online arbitrage sellers and dropshippers often lack direct product suppliers. Instead, they parse data from supplier websites to analyze products and identify profitable deals.

  • Solution

Seller Assistant API simplifies this process by providing product data through the API. Sellers can fetch ASINs, titles, pricing, and category information to efficiently evaluate and compare products from potential suppliers, saving time and effort.

Sellers need to check product restrictions and eligibility

  • Use case

Sellers need to know if a product has selling restrictions or if their account is eligible to sell it. Additionally, they must assess potential risks like whether a product is fragile, bulky, hazmat, or meltable.

  • Solution

Seller Assistant API allows sellers to instantly check product restrictions and eligibility by ASIN and marketplace. It also highlights risk factors, enabling sellers to estimate additional costs and make better sourcing decisions.

Seller Assistant API Use Cases

Seller Assistant API Use Cases

Sellers need to analyze product price history

  • Use case

Sellers want to understand how a product’s price has changed over time to avoid sourcing items with unstable pricing or unprofitable trends.

  • Solution

Seller Assistant API integrates Keepa data, giving sellers access to historical pricing trends, including Buy Box prices, average prices, and offer-specific trends over 30, 90, 180, and 365 days. This helps sellers make confident sourcing decisions.

Sellers need to estimate sales and demand

  • Use case

Sellers want to identify products with high demand and steady sales but struggle to estimate sales volume accurately.

  • Solution

Seller Assistant API provides sales estimates based on BSR (Best Sellers Rank) and ASIN. With this data, sellers can identify products with consistent demand and high sales potential.

Sellers need to monitor competition

  • Use case

Understanding the competitive landscape is essential, but monitoring FBA and FBM seller offers manually is time-consuming.

  • Solution

Seller Assistant API tracks FBA and FBM offers, seller counts, and their Buy Box percentages, and more. This data allows sellers to evaluate the competitive landscape and decide whether it’s worth competing for the Buy Box.

Sellers need to automate UPC to ASIN conversion

  • Use case

Manually retrieving data like ASINs, UPCs, EANs, or calculating profits can be repetitive and prone to errors.

  • Solution

Seller Assistant API automates these tasks by offering pre-configured API requests. Sellers can quickly retrieve data, run calculations, and integrate workflows with tools like Airtable, Zapier, or Google Sheets to maximize efficiency.

Sellers want to make profit selling in multiple marketplaces

  • Use case

Operating in different Amazon marketplaces requires sellers to verify product eligibility and adjust to regional differences.

  • Solution

Seller Assistant API supports multiple marketplaces, including the US, UK, Canada, and Europe. It ensures sellers can check restrictions, eligibility, and product risks across various regions seamlessly.

How Does Seller Assistant API Work?

To access Seller Assistant API, you must create a personal account in Seller Assistant.

Then, you need to generate your API key to securely access Seller Assistant API via your account dashboard. To request data, use pre-configured endpoints to fetch product insights, profitability calculations, stock trends, and more.

You can automate your workflow by combining Seller Assistant data with your existing tools to eliminate repetitive tasks and gain actionable insights.

Steps to get started with Seller Assistant API

Step 1. Generate your API key

Obtain your unique key from the API keys section in your Seller Assistant account to enable secure access. Head over to the API Keys page in your Seller Assistant account and generate your unique key. This key ensures secure communication with the platform. Watch a quick guide here.

Step 2. Familiarize yourself with the API documentation

Use the comprehensive API Documentation as your guide to understand available endpoints, request structures, and best practices.Take a moment to familiarize yourself with how it all works.

Familiarize yourself with the API documentation

Familiarize yourself with the API documentation

Step 3. Connect your Amazon account

Ensure your Amazon Seller Account is connected to unlock full access to data and functionalities.

Connect your Amazon account

Connect your Amazon account

Step 4. Start your integration

Use pre-configured requests and code snippets to jumpstart your integration and maximize your workflow efficiency.

FAQ

What is the Seller Assistant API?

The Seller Assistant API is a powerful tool for Amazon sellers that combines data from Keepa and Amazon SP API into one platform. It provides product insights, sales data, and profitability calculations to streamline your workflows and save time.

Who can benefit from the Seller Assistant API?

Amazon wholesale sellers, online arbitrage sellers, and dropshippers can all benefit from the Seller Assistant API. It helps with tasks like product research, analyzing profitability, checking restrictions, and automating data processing.

Can Seller Assistant API integrate with my existing tools?

Yes, the API integrates seamlessly with tools like Airtable, Make, Zapier, Excel, and Google Sheets. This eliminates repetitive tasks like syncing ASINs, refreshing product data, and exporting key insights.

How does the API estimate sales and profitability?

The API provides sales estimates based on BSR (Best Sellers Rank) and uses fees and pricing data to calculate profitability metrics like ROI and net margins. This helps sellers evaluate product demand and financial viability.

Is the Seller Assistant API easy to use for beginners?

Absolutely! The API comes with pre-configured requests and detailed documentation, making it simple to integrate and start using without technical complexity.

Can the API help dropshippers and online arbitrage sellers?

Yes, it’s perfect for dropshippers and arbitrage sellers who need to process supplier data or parse potential product lists. The API fetches product data like ASINs, pricing, and eligibility to identify profitable deals quickly.

Final Thoughts

In conclusion, Seller Assistant API is a game-changing tool for Amazon sellers, offering everything you need to streamline your workflows and make smarter, faster decisions. By integrating data from Keepa and Amazon SP API, it simplifies tasks like product research, sales estimation, profitability analysis, and competition monitoring – all while saving you time and effort.

Whether you’re a wholesale seller, online arbitrage expert, or dropshipper, the Seller Assistant API empowers you to focus on growing your business instead of getting bogged down by repetitive tasks.

Seller Assistant is an all-in-one product sourcing software offering all the features vital for product sourcing. It combines three extensions: Seller Assistant Extension, IP Alert, and VPN by Seller Assistant, tools: Price List Analyzer, Brand Analyzer, Seller Spy, Bulk Restrictions Checker, and API integrations, and features: Storefront Widget, Side Panel View, FBM&FBA Profit Calculator, Quick View, ASIN Grabber, UPC/EAN to ASIN converter, Stock Checker, and other features that help quickly find high-profit deals. Seller Assistant also offers integration with Zapier allowing to create custom product sourcing workflows.

Seller Assistant
Seller Assistant

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