Dev Toolbox

Local dev toolbox: JSON/codec/JWT/cURL/QR and more. Fully local, no upload.

Dev Toolbox bundles the everyday developer chores that usually need five different websites into one browser popup — one click away, no tab-switching. Detector reads your clipboard or current tab and routes cURL / JWT / JSON / URL / Base64 straight to the right tool. Format and validate JSON with JSONPath queries, decode JWT locally (header.payload.signature, no signature verification, nothing uploaded), convert a cURL command into fetch or axios, generate QR codes for text / URL / Wi-Fi / Email / Phone / SMS, and switch request headers per profile via declarativeNetRequest. Also included: URL & Base64 / Unicode / HTML codec, UUID v4 / password / random string generator, URL params editor with UTM helper, text stats and case transforms, plus a Unix timestamp converter. Install and use immediately — no signup, no accounts. The UI ships in 10 languages. PRIVACY: 100% local, no network requests, no backend, no tracking. Your data never leaves the browser; JWT tokens and cURL bodies live only in memory and are cleared on close. Work offline with confidence.