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Real-time rate comparison across your carrier ecosystem
Provide accurate, real-time shipping options directly in your checkout. ShipStation API compares carrier rates and delivery timing across multiple carriers, with built-in rate shopping logic to highlight the cheapest, fastest, or best-fit services—so you can confidently select the right option for every order.
Driving fulfillment for the world’s leading brands
Turn shipping rate comparison into a revenue driver
Improve conversions while lowering operational costs. ShipStation API gives you clear, actionable rate data that makes it easy to choose the most cost-effective services and automate smarter routing decisions everywhere you work.
Keep your delivery promise
Stop losing carts to unpredictable shipping fees. With ShipStation API, you can display accurate shipping costs at checkout based on exact shipment details, giving customers transparent pricing and estimated delivery details that build confidence and reduce abandonment.
Lower your cost per shipment
Compare shipping rates from all your connected carriers in a single rate request. Sort options by total cost and delivery timing to quickly identify the cheapest, fastest, or most cost-effective services. Over time, these better routing decisions translate into meaningful savings on every order.
Simplify international and cross-border pricing
ShipStation API supports shipment details that help you calculate duties, taxes, and additional fees where available. This lets you present more accurate landed costs to customers, reducing surprises at delivery and smoothing international shipping workflows.
See ShipStation API rate shopping in action
Explore our interactive tour to see how ShipStation API’s rate shopping tools can improve efficiency, reduce costs, and boost your bottom line.
Features built for real-time decisioning
Real-time rate requests from a single endpoint
Submit a single request to the ShipStation API to retrieve carrier quotes you can immediately display, store, or apply within your shipping logic. Include carrier IDs and shipment details to return pricing and delivery options from the carriers most relevant to your business.
Build shipping logic that adapts to your systems
Request rates using full shipment details or reference an existing shipment ID—whichever fits your architecture. This flexibility allows your team to support multiple workflows, avoid redundant data handling, and maintain consistent rate logic across systems without added complexity.
Present only the options that align with your business rules
Filter rate responses by service codes, package types, and approved shipping methods to ensure customers and internal teams see only relevant, supported options. This protects carrier agreements, reduces incorrect selections, and keeps shipping decisions aligned with your operational standards.
Identify cheapest and fastest options automatically
Make shipping decisions quickly without manually reviewing every quote. Use returned cost and delivery date fields to sort rates, highlight low-cost services, prioritize fast delivery options, and power smart defaults within your checkout or fulfillment tools. This speeds up operations while keeping costs under control.
Gain full visibility into your shipping costs
Move beyond a single line-item rate. When available, responses include detailed breakdowns of carrier charges such as transportation, insurance, confirmation services, and additional fees. This level of transparency supports margin analysis, streamlines reconciliation, reduces billing surprises, and gives customer service teams the clarity they need to confidently explain shipping charges.
Scale shipping rates without slowing checkout
Show customers accurate shipping costs at checkout and keep those rate details on hand for reporting, cost comparisons, and fulfillment decisions later. Combine speed, accuracy, and flexibility so your shipping logic scales smoothly as order volume and business complexity grow.
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ShipStation API removes the complexities of shipping. Scale your business with our industry-leading API, comprehensive documentation, and vast carrier network.
Shipping rates FAQs
What is an API with shipping rate capabilities? How is it different from a label feature?
A shipping rate API focuses on returning carrier quotes and delivery timing so you can compare prices and select the best service before purchasing a label. A label feature purchases the actual shipment label after you choose a rate.
Can I use ShipStation API to power my checkout shipping options?
Yes. Many teams use ShipStation API to plug shipping rate quotes directly into their ecommerce checkout. By sending cart or order details, you can retrieve real-time carrier rates and show customers options that fit their budget and delivery expectations.
Do I need to connect each carrier separately to get rates?
Only one integration with ShipStation API is required. Once your carriers are connected and configured inside ShipStation API, you can request rate quotes from one or multiple carriers in a single call — simplifying your code and avoiding multiple integrations.
Can the shipping rates feature help with duties, taxes, and fees?
Yes. When you include accurate shipment and customs details, ShipStation API can return rate responses that reflect duties, taxes, and other fees where supported — helping you present more accurate landed costs upfront.
What happens after I choose a rate from the response?
Once you select the rate that best fits your shipment, you use its details to purchase a shipping label. Because the shipment ID was created during the rate request, you can transition seamlessly from rate selection to label creation in one consistent workflow.
How fast does ShipStation API return shipping rate quotes?
ShipStation API is built for real-time workflows, returning carrier rate quotes quickly enough to power live checkout experiences and internal fulfillment tools. Performance depends on carrier response times and shipment complexity, but most teams use it successfully in customer-facing flows.
Can I compare rates across multiple carriers in a single request?
Yes. With one API call, you can request shipping rates from multiple connected carriers at once. This lets you compare prices and delivery timing without maintaining separate integrations or handling different carrier formats.
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