HTTP & REST Client - Pico API

Pico API is a lightweight HTTP client and REST API testing tool for Chrome. Send HTTP requests, debug REST APIs, and test endpoints directly in your browser — no account, no desktop app, no setup. Looking for a lightweight Postman or Insomnia alternative that lives in your browser? Fire off a quick GET request the moment the tab opens, post JSON with auth headers, and inspect the response in a fast JSON tree — the daily API testing workflow without the platform weight. WHY PICO API • Zero setup — runs in a Chrome tab, everything stored locally in your browser • Local-first & private — no analytics, no ads, no cloud sync, no account required • Small on purpose — opens instantly and stays out of your way HTTP REQUEST BUILDER • Every standard HTTP method, selectable from the built-in dropdown • Headers, query parameters, and body formats: raw JSON, XML, text, x-www-form-urlencoded, and multipart/form-data file upload • Bearer token, Basic auth, and API key authentication • Request timeout, redirect control, and browser cookie forwarding • CORS bypass via the extension service worker — test any API endpoint RESPONSE VIEWER & API DEBUGGER • Live streaming responses (SSE / chunked) rendered in real time • JSON tree viewer that stays fast on any response size, with copy-path and syntax-highlighted raw view • Response headers, cookies, timing, and size at a glance ENVIRONMENTS & VARIABLES • {{variable}} substitution across URL, headers, body, and scripts • Multiple environments (dev / staging / production) with quick switch SCRIPTS & TESTS (Postman-compatible) • Pre-request and post-response scripts with the pm.* API, running in a hardened sandbox • pm.test assertions with a pass/fail results panel • Postman-style assertions: pm.response.to.have.status/header/body, pm.expect().to.eql/include, and more • pm.sendRequest — call another endpoint from a script and reuse the result • pm.variables / pm.environment / pm.globals / pm.collectionVariables COLLECTIONS & PRODUCTIVITY • Organize requests in a searchable folder tree • Request history with one-click re-run and batch delete • Import cURL commands, OpenAPI/Swagger specs (with $ref resolution), and ApiFox projects • Export collections, copy any request as cURL • Command palette (⌘K), keyboard shortcuts, undo/redo • English & 简体中文 interface WHO IT'S FOR • Frontend and backend developers debugging internal or third-party APIs every day • QA engineers running quick checks and replaying past requests • Students and hobbyists who want a REST client that's always one tab away PRIVACY, ANSWERED • Where is my data stored? Entirely in your browser's local storage — requests, collections, and history never leave your machine. • Why the network and cookie permissions? Network access exists only to call the endpoints you choose. Cookie forwarding (on by default, so logged-in API calls just work) can be turned off in settings. • Any account, tracking, or ads? None. Pico API is free — install it and send your first request in under a minute.