tool · free · runs in your browser
Cookie Converter: Netscape ↔ JSON
Paste cookies in any format — Netscape cookies.txt, JSON from a browser extension, or a Cookie header string — and get a file that Dolphin, Octo, GoLogin or AdsPower will import. The input format is detected automatically; expired entries are highlighted.
Runs entirely in your browser: cookies are never uploaded or stored anywhere.
Paste cookies on the left — the result appears instantly.
Why convert cookies at all
Cookies come from many places: the EditThisCookie and Cookie-Editor extensions export JSON, Puppeteer and Playwright return arrays of objects with their own field names, curl and wget work with a plain-text cookies.txt, and from DevTools the easiest thing to grab is the Cookie request header. Antidetect browsers — Dolphin Anty, Octo Browser, GoLogin, AdsPower — mostly accept just two formats on import: Netscape and JSON. Feed them the wrong one and the profile ends up empty, or the import fails silently. This converter turns any of the three formats into any other while keeping domain, path, expiry and the Secure, HttpOnly and SameSite flags.
How the formats differ
Netscape cookies.txt is one line per cookie with seven tab-separated fields: domain, subdomain flag, path, Secure, expiry as unix seconds, name, value. HttpOnly is encoded as a #HttpOnly_ prefix before the domain, and 0 in the expiry field means a session cookie. JSON stores the same data as objects: expiry is a numeric expirationDate, session cookies carry a session flag, and there is a SameSite field Netscape lacks. A header string is just name=value pairs — no domain, no expiry — so when converting from it you must set the domain yourself in the "Default domain" field.
Session and expired cookies
Session cookies live until the browser closes: they are picked up on import but may vanish after a profile restart, so long-lived auth tokens matter more. Expired entries are discarded by the browser anyway, but they clutter the file and occasionally break an import — tick "Drop expired" and they are left out of the result. For the full workflow of moving cookies into a profile and warming it up afterwards, see Importing cookies into antidetect profiles: formats and warm-up, and pick the browser itself in our antidetect browser rating.