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API Request Tester
Test public REST and GraphQL APIs online with collections, environments and visual assertions. Choose Server or Browser mode; no Mayexa account required.
Choose Server or Browser request modeVersion 1.1.0
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How to use API Request Tester
- Enter a full URL and choose an HTTP method, or import cURL, Mayexa collection JSON or the supported Postman collection subset.
- Configure parameters, headers, authentication, body and visual assertions. Use {{variable}} values from the active environment.
- Click Send request or Ctrl/Cmd + Enter. Choose Server mode for public APIs without CORS; your URL, credentials and body pass through Mayexa. Browser mode sends directly and requires CORS.
- Inspect status, total time, decoded bytes, pretty/raw body, exposed headers and tests. Filter lines or inspect a JSON path.
- Pin a response for comparison, export code, or save requests to the in-memory collection. Run collection explicitly sends the saved requests sequentially.
- Save redacted local templates only after opting in. Export is redacted by default; review custom URLs and headers before sharing. Reload clears unsaved session data.
A practical example
Load the example, then explicitly send a GET to https://httpbin.org/get with a hello query parameter. Inspect the JSON response and test results.
How it works
Browser Fetch with omitted cookies, rejected redirects, AbortController timeouts and bounded streamed reads. Declarative assertions, JSON paths and structural body comparison run locally. Imports are parsed as data; no shell or user scripts are executed. Server mode uses a stateless Mayexa relay with public-IP validation and pinned connections; Browser mode sends directly. No request contents are persisted.
Limits and assumptions
Direct browser requests require CORS. Server mode relays public HTTP/HTTPS APIs on ports 80/443 through Mayexa; private addresses are blocked. Browser mode supports HTTPS or localhost HTTP. No cookies, automatic redirects or script execution. 2 MiB bodies/responses/imports; 10 tabs/environments; 50 saved requests; 100 rows/assertions; 30 session history items; runner up to 25 calls and 5 iterations; 1–60 second timeout. No multipart, OAuth exchange, WebSocket/gRPC, team sync or load testing. Browser mode exposes only CORS-visible headers; Server mode excludes Set-Cookie. Server requests: 30/minute per IP, 300/minute globally. Cancellation stops waiting but cannot undo an operation already sent. Postman import supports raw/form request subsets, not scripts/auth configuration.
Frequently asked questions
What does API Request Tester help with?
An online API tester sends an HTTP request and helps inspect the response. Mayexa supports REST requests, GraphQL JSON envelopes, environments, collections and declarative assertions. Server mode routes public API requests through Mayexa; Browser mode calls the target directly and remains subject to browser CORS rules.
What should I check before relying on the result?
POST, PUT, PATCH and DELETE can change real target data; the collection runner sends real requests sequentially. Importing a collection does not run its scripts, and this tool does not offer arbitrary JavaScript execution or full Postman parity. Local persistence and exports have explicit redaction choices. Review custom URLs and headers before sharing a template.
Do I need a Mayexa account?
No Mayexa account is required. Review the workspace's processing labels and limits before entering data.
Do I need an account or API key for Mayexa?
No. The tool is free and account-free. If your target API requires authentication, enter its credentials in the Authentication tab; they are sent only on Send/Run, through Mayexa in Server mode or directly in Browser mode.
Why does a request work in Postman but fail here?
Select Server mode to call public HTTP/HTTPS APIs through Mayexa without browser CORS restrictions. Browser mode still obeys CORS and browser network permissions. Server mode blocks private/local networks and does not follow redirects; use the final URL.
Are credentials, collections and responses stored?
Workspace data stays in browser memory and disappears on reload. In Server mode, request credentials and bodies pass transiently through Mayexa and are not stored or logged by this feature. You can explicitly save redacted templates on this device; bodies, notes, tokens, passwords and environment values are omitted. Exports include credentials and bodies only after a separate opt-in. Custom URLs and headers still need review before sharing.
Can I import Postman collections and cURL?
Yes, with visible limits. Postman v2 nested requests with raw or URL-encoded bodies and URLs are supported; scripts, files and authentication configurations are excluded. cURL supports URL, method, headers, raw body and Basic authentication. Unsupported flags are rejected instead of silently ignored.
Does the runner send real requests?
Yes, including POST, PUT, PATCH and DELETE. It runs sequentially with at most 25 calls per run, up to five iterations and a short pause between calls. Configure assertions, optionally stop at the first failure and cancel at any time. It is not a load-testing service.
Which protocols and advanced features are available?
HTTP REST, GraphQL JSON envelopes and text/XML request bodies are supported. Visual assertions and response comparison are local. There is no OAuth exchange, arbitrary JavaScript execution, multipart file upload, gRPC, WebSocket, cloud collaboration or background monitoring.
Learn the method and check the limits
Work through a practical example and understand how to interpret the result before relying on it.
Test an API Online: Server Mode, Browser CORS and Response Checks