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The eCommerce API Landscape

Best APIs for Product Data and Ordering

Best APIs for Checkout and Payment Processing

Best APIs for Managing and Fulfilling Orders

Best APIs for Post-Sale Experience

Choosing the Right API for Your Product

Overall Recommendation

Top eCommerce APIs to 10x App Development

Yee Ki Au

Growth @ Rye

7 Minutes Read

Building an end-to-end shopping experience used to take months. With APIs, adding shopping to apps is possible in a matter of days. Developers can leverage existing platforms and services as building blocks. Therefore, it's crucial to select the appropriate API stack to optimize your app's capabilities and user experience. Here’s an overview of the eCommerce API landscape, our top-picks, and how to choose the right stack for your app.

The eCommerce API Landscape

We can breakdown the shopping experience into 4 steps: listing products, processing payment, managing and fulfilling orders, and post-sale experience. Developers can take the traditional route of procuring products, stocking inventory, and building their own fulfillment chains. Alternatively, you can choose to drop ship products and let merchants handle the order fulfillment.

Here’s our top-pick APIs for each step in the shopping experience. Find your solution whether you're developing TikTok Shop, an ARVR marketplace, or creator storefronts.

Listing products to sell

  • APIs to fetch product data & programmatically order from any merchant

  • APIs to sync product data & place order from partnered merchants

  • APIs to fetch product data only

  • APIs to fetch merchant data

  • APIs to build a search experience

Processing payment

  • APIs to process payment & checkout

  • APIs to offer flexible payment options

Managing and fulfilling orders

  • APIs to for production & inventory management

  • APIs to orchestrate shipping & fulfillment

Post-sale experience

  • APIs for post-sale experience

Note: this blog focuses on solutions to build personalized and contextualized shopping experiences for end-users. We will not cover apps and APIs for merchants’ backend. Marketplace-specific APIs are available, such as Shopify Admin / Partner API, Amazon Selling Partner API, and Medusa Admin API.

Best APIs for Product Data and Ordering

APIs to fetch product data & programmatically order from any merchant

These APIs enable marketplaces to kickstart and grow. They don't require 1:1 merchant relationships and integrations, thus helping you overcome the chicken-and-egg problem.

Rye

  • Connect and automate ordering from any Amazon Business and Shopify store using Rye’s Sell Anything API. You can ingest product data by entering the variant id (ASIN for Amazon) or store URL. Also supports single checkout for shopping carts with multiple merchants / marketplaces, and fulfills orders with fast & free Prime shipping.

Zinc

Fetch product data and programmatically order from various marketplaces such as Amazon, Walmart, AliExpress. Zinc also supports crypto payments and various shipping options.


APIs to sync product data & place order from partnered merchants

If you already have merchants relationships, these APIs enable you to sync product data and automate ordering. You can even negotiate and manage affiliate commissions. However, this route requires authentication & integration with each merchant.

Rye

  • Sync real-time data, place orders, and manage affiliate commissions with Shopify brands via the Rye Sync API. Supports 2-click onboarding for your partnered merchants by installing the Rye Shopify app. Rye also has an existing catalogue of partnered merchants (e.g. RAINS, Kettle & Fire) with commissions available for developers.

Violet

  • A Unified Checkout API to onboard and checkout products from multiple merchants on major marketplaces including Shopify, WooCommerce, Salesforce, Magento, BigCommerce. Involves a multi-step technical process for merchants to onboard themselves.

Convictional

  • Integrates with merchants on Shopify, Magento, WooCommerce, and BigCommerce. It also supports fast 10-day onboarding and automated vendor payouts.

Mirakl

  • Enables marketplaces by sourcing partner dropshippers and third-party dropshippers to build distribution channels and automate wholesale, manufacturing, and retail operations.

Marketplace-specific integrations

  • Most marketplaces offer APIs that provide read-only access to specific merchant’s store data and automate ordering. This includes the Shopify Storefront API, Salesforce Commerce API, Amazon SP API, Medusa Store API, Magento Storefront API, eBay Browse API, and AliExpress API.

APIs to fetch product data only

Access web-scraped, up-to-date product data that you can simply plug-and-play for your app’s inventory. Note that these APIs do not have the rails to programmatically send orders back to merchants.

Rainforest

  • Offers integration with their web-scraped Amazon product data using their API, including product information, images, pricing, and availability etc.

Axesso

  • Sync Axesso’s web-scraped product data from Amazon, Walmart, Otto, Alibaba, etc. They also offer data from social media sources like Facebook and Instagram.

APIs to fetch merchant data

Bonus category of APIs that give you metadata on eCommerce merchants. Although not essential for building your MVP shopping experience, they are useful starting points for your product search and help you monitor eCommerce trends.

Store Leads

  • REST APIs to query their database of information on over 12mil eCommerce stores, with over 40 attributes tracked.

Charm.io

Integrate and query Charm’s database of over 4mil eCommerce stores including growth trends and successful brands.

APIs to build a search experience

Enable shoppers to discover their desired products. Maximize conversion and AOV.

Algolia

  • Integrate AI-powered, personalized product search and recommendation for your app. Algolia API offers search-as-a-service, readily integrated with most marketplaces like Shopify, BigCommerce, Magento, and Salesforce.

Shopify

  • The Product Recommendations API allows businesses to incorporate personalized product recommendations throughout the shopping journey, suggesting related or complementary items to customers.

Best APIs for Checkout and Payment Processing

APIs to build a checkout flow

Securely process transactions and ensure friction-free checkout by accepting the shoppers’ preferred payment methods. These APIs handle the complex tasks of payment validation, encryption, and communication with payment gateways, whilst ensuring your compliance.

Stripe

  • Comprehensive suite of Checkout, Payments, and Subscriptions APIs for customizable payment flows. Stripe’s Billing API also enables businesses to create and manage subscriptions, including recurring billing and subscription-based services.

Bold

  • Checkout APIs to build customizable checkout flows. Also offers Upsell API, Subscriptions API, and Product Bundles API, as well as Price Rules API to manage promos.

Rye

  • Rye Pay accepts payments via Visa, Master, Amex cards. Flexible and secure payment flows to ensure you are compliant. Apple Pay and one-click checkout are coming soon.

Paypal

  • Integrate PayPal as a payment option with their APIs such as PayPal Checkout and PayPal Payments Pro. They support international transactions.

Adyen

  • Ayden Explorer allows businesses to accept a wide range of payment methods and supports payouts and recurring payments.

ReCharge

  • The ReCharge API enables you to offer subscription services, recurring billing, and targeted customer journeys to maximize LTV. It allows you to setup payment gateways including Stripe and Paypal.

APIs for flexible payment plans

Klarna

  • Increase conversion by offering flexible payment options including pay later, pay in installments, financing, or direct payments.

Afterpay

  • Buy now, pay later platform for customers to split their purchases into interest-free installments to suit their needs.

APIs to build a checkout flow

Securely process transactions and ensure friction-free checkout by accepting the shoppers’ preferred payment methods. These APIs handle the complex tasks of payment validation, encryption, and communication with payment gateways, whilst ensuring your compliance.

Stripe

  • Comprehensive suite of Checkout, Payments, and Subscriptions APIs for customizable payment flows. Stripe’s Billing API also enables businesses to create and manage subscriptions, including recurring billing and subscription-based services.

Bold

  • Checkout APIs to build customizable checkout flows. Also offers Upsell API, Subscriptions API, and Product Bundles API, as well as Price Rules API to manage promos.

Rye

  • Rye Pay accepts payments via Visa, Master, Amex cards. Flexible and secure payment flows to ensure you are compliant. Apple Pay and one-click checkout are coming soon.

Paypal

  • Integrate PayPal as a payment option with their APIs such as PayPal Checkout and PayPal Payments Pro. They support international transactions.

Adyen

  • Ayden Explorer allows businesses to accept a wide range of payment methods and supports payouts and recurring payments.

ReCharge

  • The ReCharge API enables you to offer subscription services, recurring billing, and targeted customer journeys to maximize LTV. It allows you to setup payment gateways including Stripe and Paypal.

APIs for flexible payment plans

Klarna

  • Increase conversion by offering flexible payment options including pay later, pay in installments, financing, or direct payments.

Afterpay

  • Buy now, pay later platform for customers to split their purchases into interest-free installments to suit their needs.

Best APIs for Managing and Fulfilling Orders

APIs for production & inventory management

Ensure your stock levels are up-to-date and the latest information is synced. These APIs help you reduce manual work and human error. They often also support order management and fulfillment.

Fulfil.IO

  • Comprehensive features including order management, inventory management, and manufacturing and production tracking, providing end-to-end visibility and scalability. Supports updates across multiple platforms, including 3PL, various shipping carriers, warehouse, retail location, and suppliers.

TradeGecko

  • Inventory management software that provides features like centralized inventory tracking, order fulfillment, and warehouse management, to help businesses streamline inventory management.

Extensiv

  • Integrates order management, inventory control, fulfillment, and analytics such as demand forecasting. Supports multiple eCommerce platforms, sales channels, and shipping carriers as well.

Fishbowl

  • Emphasizes on manufacturing and warehouse management. Offers features like materials bills, work orders, lot tracking, and barcode scanning. Suitable for businesses with complex manufacturing processes.

Katana

  • Manufacturing and inventory management software designed for small and medium-sized businesses. Offers features like production planning, inventory optimization, and real-time tracking of manufacturing processes.

Printful

  • RESTful API to access their white-label product marketplace. Suitable for drop shipping products customized to order.

APIs to orchestrate shipping & fulfillment

Use APIs to connect with fulfillment providers and automate the process. This includes generating shipping labels, status updates, and shipping rate calculation.

Fulfil.io, TradeGecko, Extensiv

  • Production and inventory management software that have integrated fulfillment and tracking functionalities.

Shippo

  • Simplify the process of integrating multiple carriers, allowing businesses to compare rates, generate shipping labels, track packages, and streamline your shipping operations. They support address validation, batch processing, and international shipping.

Easypost

  • A unified interface to access multiple carriers, enabling them to automate shipping label generation, track packages, and manage their shipping processes efficiently, including returns.

Aftership

  • Allows developers to integrate real-time shipment tracking and delivery status notifications from various couriers and carriers into their app for full visibility

DHL, UPS, FedEx, USPS

  • Global shipping and logistics companies often offer APIs to integrate services into business applications. This includes access to international shipping, parcel tracking, and other logistics solutions.

APIs for production & inventory management

Ensure your stock levels are up-to-date and the latest information is synced. These APIs help you reduce manual work and human error. They often also support order management and fulfillment.

Fulfil.IO

  • Comprehensive features including order management, inventory management, and manufacturing and production tracking, providing end-to-end visibility and scalability. Supports updates across multiple platforms, including 3PL, various shipping carriers, warehouse, retail location, and suppliers.

TradeGecko

  • Inventory management software that provides features like centralized inventory tracking, order fulfillment, and warehouse management, to help businesses streamline inventory management.

Extensiv

  • Integrates order management, inventory control, fulfillment, and analytics such as demand forecasting. Supports multiple eCommerce platforms, sales channels, and shipping carriers as well.

Fishbowl

  • Emphasizes on manufacturing and warehouse management. Offers features like materials bills, work orders, lot tracking, and barcode scanning. Suitable for businesses with complex manufacturing processes.

Katana

  • Manufacturing and inventory management software designed for small and medium-sized businesses. Offers features like production planning, inventory optimization, and real-time tracking of manufacturing processes.

Printful

  • RESTful API to access their white-label product marketplace. Suitable for drop shipping products customized to order.

APIs to orchestrate shipping & fulfillment

Use APIs to connect with fulfillment providers and automate the process. This includes generating shipping labels, status updates, and shipping rate calculation.

Fulfil.io, TradeGecko, Extensiv

  • Production and inventory management software that have integrated fulfillment and tracking functionalities.

Shippo

  • Simplify the process of integrating multiple carriers, allowing businesses to compare rates, generate shipping labels, track packages, and streamline your shipping operations. They support address validation, batch processing, and international shipping.

Easypost

  • A unified interface to access multiple carriers, enabling them to automate shipping label generation, track packages, and manage their shipping processes efficiently, including returns.

Aftership

  • Allows developers to integrate real-time shipment tracking and delivery status notifications from various couriers and carriers into their app for full visibility

DHL, UPS, FedEx, USPS

  • Global shipping and logistics companies often offer APIs to integrate services into business applications. This includes access to international shipping, parcel tracking, and other logistics solutions.

Best APIs for Post-Sale Experience

APIs for post-sale experience

Zendesk

  • Integrate customer support and service functions including managing customer queries, support tickets, and communication post-purchase.

Yotpo

  • Facilitate the collection and management of customer feedback and product reviews.

LoyaltyLion

  • Building customizable loyalty and rewards programs to encourage repeated purchases.

Rye

  • Provide tracking updates via web hooks and manage cancellations and refunds in one place.

Klaviyo

  • Automate email marketing and customer re-engagement campaigns.

APIs for post-sale experience

Zendesk

  • Integrate customer support and service functions including managing customer queries, support tickets, and communication post-purchase.

Yotpo

  • Facilitate the collection and management of customer feedback and product reviews.

LoyaltyLion

  • Building customizable loyalty and rewards programs to encourage repeated purchases.

Rye

  • Provide tracking updates via web hooks and manage cancellations and refunds in one place.

Klaviyo

  • Automate email marketing and customer re-engagement campaigns.

Choosing the Right API for Your Product

Benefits of APIs

APIs allow your app to directly connect with pre-built functionalities and endpoints to save development time and resources. Integrating with services like payment gateways and shipping providers also helps you quickly enhance your product.

More importantly, APIs power a seamless experience for end-users. 97% of consumers have backed out of a purchase because the service was inconvenient. APIs tackle this by enabling a frictionless user journey within your app from product discovery to checkout. They also ensure consistency in synchronizing data across and within systems.

What should you look out for?

  1. Evaluate the reliability and stability of the API provider. Look for established providers with a track record of delivering consistent performance and uptime.

  2. Consider the scalability and flexibility of the API to accommodate your product's growth and future needs. Ensure that the API offers comprehensive developer support and is able to handle your product's expected workload.

  3. Assess the pricing structure and terms to ensure it aligns with your business model and budget.

  4. Emphasis on data security with robust authentication and authorization mechanisms. Look for features like encrypted communication, token-based authentication, and adherence to industry-standard security protocols.

  5. Ensure that the API is compatible with your existing technology stack and infrastructure. Assess the programming languages, frameworks, and platforms that your product relies on.

Benefits of APIs

APIs allow your app to directly connect with pre-built functionalities and endpoints to save development time and resources. Integrating with services like payment gateways and shipping providers also helps you quickly enhance your product.

More importantly, APIs power a seamless experience for end-users. 97% of consumers have backed out of a purchase because the service was inconvenient. APIs tackle this by enabling a frictionless user journey within your app from product discovery to checkout. They also ensure consistency in synchronizing data across and within systems.

What should you look out for?

  1. Evaluate the reliability and stability of the API provider. Look for established providers with a track record of delivering consistent performance and uptime.

  2. Consider the scalability and flexibility of the API to accommodate your product's growth and future needs. Ensure that the API offers comprehensive developer support and is able to handle your product's expected workload.

  3. Assess the pricing structure and terms to ensure it aligns with your business model and budget.

  4. Emphasis on data security with robust authentication and authorization mechanisms. Look for features like encrypted communication, token-based authentication, and adherence to industry-standard security protocols.

  5. Ensure that the API is compatible with your existing technology stack and infrastructure. Assess the programming languages, frameworks, and platforms that your product relies on.

Overall Recommendation

Rye as a simple yet hyper-customizable API to grow with your platform. With Rye, you unlock the ability to access inventory data for any Amazon Business and Shopify products, programmatic ordering, payment integration, and earn affiliate commissions. The APIs are suitable for developers looking to streamline their tech stack and solving the chicken-and-egg problem.

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