HeaderDeck — Modify HTTP Headers

Modify, add or remove HTTP request & response headers. Profiles, URL filters, import/export. Local-only. No account, no tracking.

HeaderDeck lets you modify, add, or remove HTTP request and response headers — the fast, private way to test APIs, debug CORS, spoof environments, and more. ★ WHY HEADERDECK • Local-first — your profiles never leave your browser • No account, no sign-up, no analytics, no tracking • One-click import from ModHeader — switch without losing your setup • Lightweight: uses Chrome's native declarativeNetRequest (no traffic interception) ★ FREE, FOREVER • Up to 3 active profiles • Unlimited headers per profile • Set, append or remove — request AND response headers • URL filters with wildcards • Import and export your data as JSON, any time • Light and dark theme, keyboard shortcut to pause everything ★ PRO (optional) • Unlimited profiles • Sync profiles across your devices (via Chrome's own account sync — still no server of ours) • Paste headers straight from a cURL command or DevTools • Regular-expression URL filters Monthly, yearly, or a one-time lifetime licence — your choice. Anything you create on the free plan stays yours. Extra profiles above the free limit are never deleted or hidden — they simply aren't applied until you upgrade. We will never take away something that used to be free. ★ PERFECT FOR • Developers testing APIs with auth tokens • QA engineers switching between test accounts • Debugging CORS, cache, and security headers • Anyone who needs custom headers on specific sites ★ PRIVACY HeaderDeck requires header and storage permissions only to do its job. It contains no analytics and no tracking, and your configuration stays on your device. If you buy Pro, the payment is handled by ExtensionPay and Stripe — we never see your card details. Full policy: [odkaz na PRIVACY.md] Questions or feature requests? https://github.com/kanskyalexandr-ext/headerdeck/issues