Rewire – Modify Headers, Cookie Editor & Network Inspector

Modify HTTP request & response headers, edit and export cookies, switch accounts and inspect network headers. Private, 100% local.

Rewire is a private, all-in-one HTTP header editor, cookie editor and network inspector for developers, QA and security testers. Modify request headers and response headers, override cookies, switch between logged-in accounts, and see exactly what every API request sent — with proof that your rules actually applied. 100% local. No account, no ads, no analytics, no remote code. Rewire's pages run with a Content Security Policy of connect-src 'none', so the browser itself blocks any network call. ★ MODIFY HEADERS • Add, set, append or remove any HTTP request header or response header • Profiles for dev, staging and prod — run several at once, drag to set priority • Filter by URL pattern, regex, domain, excluded domains, resource type (XHR/fetch, document, script…) and request method • Scope a profile to this tab, this window, a tab group, or tabs showing a site • Variables and environments: Authorization: Bearer {{token}} — switch Staging/Prod in one click • Presets: Enable CORS, disable cache, remove CSP / X-Frame-Options, mobile user agent, X-Forwarded-For, DNT/GPC, Bearer token • Redirect URLs (regex with $1 capture groups), add/remove query parameters, block requests • Timers: turn a profile on for 15 min / 1 h / until the browser closes — no more forgotten headers ★ PROOF IT WORKS (no more "is my header being sent?") • Live hit counter and sparkline on every rule • One-click diagnosis explains why a rule isn't matching: filters, resource type, site access, higher-priority profile, Chrome's append rules, or a conflicting extension • "Verify with Chrome" confirms matches using Chrome's own rule engine • Toolbar badge shows how many requests Rewire changed on the current tab ★ COOKIE EDITOR & MANAGER • View, search, add, edit and delete cookies — including HttpOnly, SameSite and partitioned (CHIPS) cookies • This page / whole site / every cookie in the browser • Live cookie activity feed: see every cookie set, deleted or expired as it happens • Protect a cookie: Rewire restores it if a site deletes or changes it • Built-in JWT decoder with expiry countdown for cookies and Authorization headers • Export cookies as JSON (EditThisCookie / Cookie-Editor compatible), Netscape cookies.txt (curl, wget, yt-dlp), Cookie header string or curl -b — with optional password encryption • Import JSON or cookies.txt from other tools ★ COOKIE JARS — SWITCH ACCOUNTS IN ONE CLICK Save every cookie for a site as a named jar ("Admin", "Customer"), log in as someone else, save again, then switch between accounts instantly. Perfect for QA and multi-account testing. Stored only on your device. ★ NETWORK INSPECTOR — ALWAYS RECORDING • Hit an error before opening DevTools? Rewire already recorded it: every request and API response is kept in the background, even across page reloads, and erased when you close the browser • Live list of requests with status, method, type and timing — in the popup, side panel or a full tab • Request and response headers with a before/after diff of what Rewire changed • Parsed request cookies and Set-Cookie attributes • Filter with method:POST status:4xx domain:api, or show only requests Rewire modified • Copy as cURL or fetch(), export HAR • Pin any header from a real request as a rule in one click • DevTools panel shows response bodies (no debugger banner) ★ PASTE ANYTHING → RULES Paste a cURL command ("Copy as cURL" from DevTools), raw headers, a HAR entry, a fetch() call, a cookie string or a Set-Cookie line anywhere in Rewire — it becomes rules instantly. ★ SWITCHING FROM ANOTHER TOOL? Import profiles from ModHeader, Requestly, Header Editor and SimpleModifyHeaders exports — paste the JSON or pick the file. A private ModHeader alternative and EditThisCookie alternative that won't be sold to an ad company. ★ KEYBOARD-FIRST ⌘K / Ctrl+K command palette ("authorization: Bearer …" adds a header instantly), Alt+Shift+R to open, Alt+Shift+P to pause everything. ★ PERMISSIONS, EXPLAINED Site access is optional — grant one site or all sites. declarativeNetRequest applies your rules; webRequest (observe-only) powers the inspector and counters; cookies powers the cookie editor. Full explanation inside Settings › Privacy & trust.