API & Backend
13 toolsBuild, inspect and document HTTP requests, tokens, webhooks and mock responses.
Everything around an HTTP request that is not the request itself: building it, reading the token it carries, understanding the status code that came back, and documenting the endpoint afterwards.
The JWT tools are the ones worth knowing about — a token is only base64, so anyone holding one can read its claims. Decoding your own is the quickest way to see what your auth layer is actually asserting.
API Request Builder
Compose method, URL, headers and body, then send or export the request.
cURL Generator
Turn a method, URL, headers and body into a ready-to-run cURL command.
HTTP Status Code Explorer
Search every HTTP status code with meaning, cause and how to respond.
JSON Path Tester
Run JSONPath expressions against a payload and see matches live.
JWT Generator
Sign HS256, HS384 or HS512 JSON Web Tokens from a payload and secret.
JWT Inspector
Decode a token and audit its claims, expiry and signature settings.
Webhook Payload Viewer
Pretty-print and explore raw webhook bodies from any provider.
Request Header Inspector
Parse raw HTTP headers and see what each one actually does.
API Mock Response Generator
Generate realistic fake JSON responses from a simple field schema.
REST Endpoint Documentation Generator
Turn an endpoint definition into clean Markdown API documentation.
What Is My IP?
See your public IP address, whether you are on IPv4 or IPv6, and what your browser reveals.
IP Address Checker
Validate any IPv4 or IPv6 address and see what it is — public, private, loopback or reserved.
IPv4 / IPv6 Checker
Tell IPv4 and IPv6 apart, expand or compress an IPv6 address, and check either one is valid.
How these tools work
12 of these tools run entirely in your browser. There is no account to create, no file to upload and no daily limit, because the work happens on your own device rather than on a server — which also means there is nothing for us to log, cache or leak. Most of them keep working with the network off once the page has loaded.
One needs our server to do its job, and says at the top of its page exactly what it sends. The Privacy Policy says what happens to it.
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