A Free API Testing Tool

API Tester


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Tatum is the World's Leading Blockchain API Provider

Our mission is to ensure any developer can build Web3 applications with no blockchain experience.

100+ Supported Protocols

Whichever chain's data you need to access, we have it indexed for you to use instantly.

API's for Anything and Everything

Whatever it is you need, Tatum's data API's make it easy to get blockchain data.

Why Developers Build With Tatum

"Tatum helps us build robust product solutions in a fraction of the time."
zac barron

Zac Barron
Product Lead at Binance

"Building a product in the crypto space is hard. Making it work reliably across chains - even harder. Tatum helped us meet our deadline."
david spiltzer

David Spitzer-Dulagan
CTO at Limewire

"Tatum accelerates our web3 development."
hitoshi harada

Hitoshi Harada
Co-founder & CPO at Alpaca

API Tester FAQ

What is an API tester?

An API tester is a tool that allows developers to send requests to and receive responses from an API (Application Programming Interface) to ensure it behaves as expected. It typically provides a user interface where you can enter the API's endpoint URL, set the HTTP method (such as GET, POST, PUT, DELETE), and include any headers or body data required for the request. The tester then displays the response from the API, including data, status codes, and headers. This aids in debugging, development, and testing of APIs by simulating the calls that client applications would make, and is essential for ensuring that the API meets its design specifications and correctly handles all possible inputs and scenarios.

How to test an API?

To test an API, you first determine the endpoints you need to test and the expected outcomes for your requests. Using a testing tool, you send HTTP requests to these endpoints with appropriate methods (GET, POST, PUT, etc.), including any necessary headers, authentication, or body data. You then verify the response to ensure the status code is correct and the returned data matches expected results. This can include checking the structure of the JSON or XML, the data accuracy, and the performance of the API. Testing should cover a variety of scenarios, including valid and invalid inputs, to fully ensure the API behaves as intended under different conditions.

API testing best practices

API testing best practices involve thoroughly planning your test cases to cover all facets of the API, including functional correctness, performance reliability, and security compliance. This includes validating response codes, response times, rate limits, and error codes for various scenarios. Tests should simulate real-world usage, considering all possible parameter combinations, including edge cases. It’s also crucial to automate your tests to run in different environments and include them as part of your CI/CD pipeline to ensure continuous testing throughout the development lifecycle. Moreover, maintaining clear documentation and versioning is essential to track changes and understand the API's behavior. Lastly, it’s important to respect privacy and legal constraints, especially when handling personal data, to ensure your API testing adheres to data protection standards.