Auth Tokens is part of DevStudio — a free, in-browser collection of developer utilities that work without sign-up, installation, or any backend service. RFC 6238 TOTP / RFC 4226 HOTP generator + verifier and CSPRNG-backed OTP backup codes, all running entirely on your device. Because the page never uploads what you paste, you can run sensitive payloads, configuration files, secrets, or production data through it with confidence: nothing leaves your browser tab. Use Auth Tokens for ad-hoc debugging, code review, log triage, release prep, learning a new format, or as a quick scratchpad while you build. If you use this tool a lot, pair it with Hash, HMAC, JWT, and the rest of the DevStudio toolkit for related developer workflows.