DevLens — Developer Multi-Tool

Offline dev utilities: JSON, JWT, base64, URL, hash, UUID, timestamp & diff. 100% client-side, no data leaves your browser.

DevLens is a fast, offline developer multi-tool in your toolbar. Every tool runs 100% in your browser — your data never leaves your machine and the core tools make no network calls. Tools: • JSON — beautify, minify, validate (with error position) • JWT — decode header & payload, see expiry at a glance • Base64 — encode/decode (standard & URL-safe) • URL — encode/decode + parse query strings • Hash — SHA-1, SHA-256, SHA-512 • UUID — generate v4 identifiers • Timestamp — convert Unix ⇄ ISO 8601 • Diff — quick line-by-line comparison No accounts, no content tracking. Free to use, with an optional one-time Pro upgrade that unlocks JWT, hashing, and diff. Built for developers who want everyday encode/decode/format utilities one click away — without pasting sensitive data into random websites.