From startups to enterprises, APIs are the connective tissue of modern software. But an API is only as good as the tools used to build and test it.
With virtually every online process now using some element of AI or automation, we need effective, efficient API testing tools and platforms for API development more than ever. With that in mind, we’ve looked into the top API development and testing tools on the market to help you choose the best APIs for your business.
Table of Contents
What is API Testing?
Let’s start with some basics. API testing is all about checking how an API behaves. So looking at how well it performs, how reliable it is, and whether it’s secure to handle all your data. API testing tools send requests to an API and review the responses to make sure everything works the way it’s supposed to.
The goal is pretty straightforward: confirm that the API meets its requirements and behaves as expected for whatever you need it to do. Strong API testing will give your team confidence in the quality and stability of what they’re building. It helps catch issues early in the development cycle, reducing the risk of failures or security gaps later on.
With solid testing in place, teams can release APIs that are stable, secure, and ready for use in the real world.
The Best Tools for API Development
From design to debugging, the API lifecycle relies on the right set of tools. Depending on what kind of data and task flow your team manages, you might need to hunt around to find an API dev tool that does what you need it to.
We’ve outlined some of the top options below, so you can get a taste of what they offer.
Hoppscotch
Hoppscotch is an open-source API development platform built to be fast, lightweight, and easy to work with. It lets developers send requests in real-time and quickly review the responses, making it simple to test and explore any API. You can use all the common HTTP methods; GET, POST, PUT, PATCH, DELETE, and more, including custom requests when you need them.
The interface is flexible and easy to tailor for whatever your needs are. You can switch between different themes, adjust accent colours, and make the workspace feel the way you like it. Hoppscotch also includes helpful features such as documentation panels, headers and parameter controls, request body options, collections, pre-request scripts, and handy keyboard shortcuts.
You can even install Hoppscotch as a Progressive Web App. This gives you offline access and keeps resource use low, so it runs smoothly without putting pressure on your system.
Postman
Postman is one of the most widely adopted platforms in the industry because it supports almost every stage of API development. It provides a clean environment for designing new APIs, creating mock servers, reviewing documentation, and running exploratory or manual tests.
Its collaborative workspaces make it easy for teams to share collections, organise components, and integrate directly with CI/CD pipelines. While Postman is often associated with testing, many teams rely on it just as heavily for design and everyday development tasks.
Swagger
Swagger is a full toolkit for designing, documenting, and running APIs at scale. It’s built around the OpenAPI specification, giving developers a clear way to define resources and generate client SDKs or server stubs. So for your boots-on-the-ground teams, it’s a useful tool for saving time and reducing repetitive work during development.
The platform includes a powerful editor that shows errors as you write and presents API operations in a clean visual layout, making complex designs easier to understand. Swagger also works with a range of API gateways, including IBM, Apigee, AWS, and others, so it’s easy to integrate with any other platforms you already use.
For teams, SwaggerHub adds a shared workspace where people can collaborate, review changes, and move API projects forward more efficiently.
Insomnia
Insomnia is a design-focused platform that gives developers the tools they need to build APIs that match their business requirements. It supports SOAP, gRPC, GraphQL, and REST requests, and makes it easy to design APIs using the OpenAPI specification so teams can keep their work consistent.
The platform includes several other useful features like live previews, Git integration, and a CLI tool, all wrapped in an interface that’s refreshingly simple to navigate. It also supports a wide range of plugins, so your developers can tailor the workspace to their needs. Insomnia is free to download, with extra features available through paid plans, so it’s a good option for smaller budgets.
Sandbox
Although Sandbox is sometimes categorized as a testing tool, its strongest value lies earlier in the development cycle. It allows teams to simulate APIs, generate mock services from existing documentation, and mirror real application behaviour.
By doing this, Sandbox helps catch integration issues before proper testing begins, making it particularly useful for teams that need reliable, repeatable mock environments during development.
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Book a demoWhat are the Best API Testing Tools?
So now you’ve got some of the top API developer options, but what about API testing tools? Teams approach API testing in different ways, so the “best” tool often comes down to what fits your setup.
The following tools are popular across the industry and can help you validate behaviour, troubleshoot issues, and keep your APIs running as expected.
| Tool | Best For | Price Model | Key Feature |
| ContextQA | Automated testing, regression testing and AI-assisted updates | Paid (demo available) | Low-code test creation + AI-driven test case impact detection |
| SoapUI | Functional API testing for REST, SOAP, GraphQL | Free (Open Source) + Paid Pro | Robust GUI for complex functional and security tests |
| LoadView | Load and performance testing | Paid | Real traffic simulation for scalability and SLA validation |
| Hurl | Lightweight CLI-based testing | Free | Fast, text-based HTTP testing with JSONPath/XPath assertions |
| HTTPIE | Developer-friendly manual/API exploration via CLI | Free | Clean, readable output and intuitive command syntax |
| Hoppscotch | Manual API exploration, quick design checks | Free | Lightweight, web-based tool with PWA support |
| Postman | API design, manual testing, collaboration | Free & Paid tiers | All-in-one workspace for design, mocking, and exploratory testing |
| Swagger / SwaggerHub | API design-first workflows | Free & Paid | OpenAPI-driven design, documentation, and collaboration |
| Insomnia | API design + manual testing with Git workflows | Free + Paid | Supports REST, GraphQL, gRPC, SOAP with plugin ecosystem |
| Sandbox | Mocking and simulation during development | Free | Real-time API simulation to catch integration issues early |
ContextQA
Tools like Postman or SoapUI work well for manual API checks, but ContextQA is designed for teams that need to scale automated testing. It is a low-code platform that uses generative AI to create, maintain, and update test cases with far less manual work than traditional tools.
When an API schema or workflow changes, most test suites break and require time-consuming updates. ContextQA identifies what has changed and shows which test cases are likely to fail. Its self-healing system then suggests accurate updates that can often be applied in a single click. This helps teams avoid unnecessary failures and reduces the time spent on maintenance.
ContextQA connects with common project tools such as Jira, Asana, and Monday.com. It also integrates with CI and CD platforms including Jenkins, CircleCI, GitHub Actions, and Harness. With these integrations, tests can run automatically with each pull request or deployment, supporting continuous testing across the development process.
So, why choose it? If your team spends more time repairing broken tests than building new features, ContextQA offers a stable and efficient way to keep coverage high, reduce errors, and support reliable releases.
SoapUI
SoapUI is a well-known API testing tool for testing SOAP, GraphQL, and REST APIs. It gives developers the tools to build, manage, and run a wide range of tests, including data-driven checks, security tests, and detailed reporting.
Its interface is easy to pick up, and it offers clear visibility into how an API behaves. SoapUI also fits neatly into lots of development pipelines, making it simple to include testing as a regular part of the workflow.
The tool is open-source and supported by an active community. A selection of plugins and extensions further expands what it can do, giving teams room to tailor it to their needs.
LoadView
LoadView is a load-testing tool designed to show how an API performs when traffic starts to climb. It works with RESTful APIs, XML, JSON, and SOAP, giving teams the freedom to simulate different levels of demand, uncover bottlenecks, and check whether SLAs and capacity plans hold up.
The API platform offers flexible performance-testing options and fits easily into DevOps workflows. It also provides clear, detailed reports that help teams understand where issues might appear. With LoadView in place, developers can confirm that their APIs handle heavy traffic reliably and deliver a smooth experience for users.
Hurl
Hurl is a command-line tool that lets developers run HTTP requests using a simple text-based format. It can be used to perform full HTTP sessions, check queries, and capture both headers and response bodies.
The API testing tool supports a range of predicates and query types, including JSONPath and XPath, so you can validate status codes, headers, and other response details. Built in Rust, Hurl is fast, lightweight, and efficient, making it easy to slot into existing workflows.
Its straightforward approach to testing HTTP requests gives developers a quick way to run checks and pull the data they need, which is why it’s become a useful option for many teams working with APIs.
Also Read –“Ready for API Testing?” Here’s what you need to know first- Part 2
HTTPie
HTTPie is a command-line tool for testing APIs and HTTP servers. Its goal is to make sending requests and reviewing responses simple and efficient, without the usual complexity that comes with command-line utilities.
Developers can use it to send any type of HTTP request, upload files, submit forms, and handle authenticated calls. It supports JSON out of the box and formats responses with clear, colour-coded output that’s easy to read in the terminal.
Installation is quick on most operating systems, and the syntax is straightforward, which makes it accessible even for beginners. HTTPie also integrates well with common development tools, adding to its popularity among teams that rely on fast, reliable API testing.
Also Read – API Testing Made Fun and Easy: Dive into Part 1 Now!
Final Thoughts
API testing tools (and development platforms) sit at the core of reliable software. With the right tools in place, teams can build flexible, scalable systems that interact smoothly with other services and deliver a stable experience for users.
The tools we’ve covered each bring something valuable to the table. Used well, they help developers ship stronger APIs and reduce the risk of surprises once products go live.
Try One of the Best New API Testing Tools With a Free Demo
If you’d like to see why ContextQA is a great choice for API testing tools, book a demo to get started. It’s a relaxed, no-pressure session where you can explore the platform and get answers tailored to your setup.
