API testing
Build, run, and schedule API tests your whole team can share.
Organize requests into collections and environments, assert on every response, and run whole collections as test suites on demand or on a schedule. Intercept traffic to mock endpoints and inject failures.
Pick a request to send
Secrets filled on the server, never in the browser
- DNS 6 ms
- Connect 12 ms
- TLS 20 ms
- Waiting 128 ms
- Download 18 ms
- Status is 201Passed
- Body has an orderIdPassed
POST /v1/checkout: 201 Created in 184 milliseconds, 2 of 2 tests passed.
Collections and environments
Shared collections, per-environment variables, and team secrets that stay encrypted on the server.
Suites on a schedule
Run a collection on demand or on a schedule, with reports and Slack or Discord notifications.
Mocks and fault injection
Intercept requests to mock endpoints, redirect routes, and inject latency or failures.
What you can do today
- Send HTTP and GraphQL requests through a secure server-side proxy
- Attach files from your computer or uploaded to the cloud
- Write pre-request scripts and tests, and assert on status, headers, and body
- Run collections with iterations and export the results
- Paste a cURL command, audit it, and export it as client code
Built for teams
- Team workspaces with viewer, editor, admin, and owner roles
- Secrets resolved on the server, never sent to the browser
- Every request checked against private-network (SSRF) rules
In the product
The tools behind this page.
Each of these is available in Testnir today.
- API TesterSend HTTP requests through a secure proxy, organize them into collections & environments, assert on responses, run whole collections as test suites with reports, and let AI write and explain your tests.
- API StudioPaste a cURL command, build a request visually, or describe it in plain English. Then send it, audit it for security and reliability, and ship it as production-ready code.
- API InspectorIntercept requests and rewrite them on the fly: mock endpoints that do not exist yet, redirect a route to staging or localhost, inject or strip headers, and inject latency and failures to test how your app copes.
- JSON ToolsFormat, minify, repair & validate JSON; sort/flatten keys, JSONPath query, and convert to YAML, TypeScript, Go, CSV, XML & JSON Schema with live stats.
- JWT Encoder & DecoderDecode, inspect, sign, and verify JWTs - HMAC, RSA & ECDSA, fully in-browser.
See whether Testnir fits your team.
Book a demo of the platform, discuss a testing project, or both. We will reply by email to plan the conversation.