JWT Decoder — Base64, UUID, JSON Formatter Toolkit

JWT decoder plus Base64, JSON formatter, UUID generator, URL decode, hash & timestamp tools. Right-click any string to auto-decode.

Nine decoders. One right-click. Zero network. Decoder Toolkit is a fast, fully local developer multitool that packs nine string utilities one click away in your toolbar — plus a right-click that figures out what you selected. Highlight a token in a log, an API response or a GitHub issue, choose "Decode with Toolkit", and it detects the format automatically and opens the right tool with your value already decoded. No more pasting text between five tabs or guessing which tool you need. Everything runs inside your browser. Your tokens, secrets and data never leave your machine: no servers, no network requests, no analytics and no account. 🖱️ Right-click any string — we detect the format The auto-detecting right-click classifies JWT, Base64, JSON, URL-encoded strings, UUID, timestamps and hex colors the moment you select text. Dark mode by default, with light and system themes. Keyboard shortcuts open the popup straight to the tool you need. Monospace, color-coded output following the jwt.io convention for the token segments. 🔑 Decode a JWT and catch an expired token Paste a JSON Web Token into the JWT decoder and read the header, payload and signature as separate, color-coded sections. Time fields (iat, exp, nbf) are shown in plain language and an expired token is flagged red the moment you decode it. The fastest way to decode JWT and catch an expired claim. 🔤 Base64 decode and encode, UTF-8 safe A full Base64 decoder and encoder — Base64 decode and encode with UTF-8 support and a URL-safe variant for tokens and query strings. 🧩 Format and beautify messy JSON A JSON formatter and beautifier that turns minified JSON into a readable, collapsible tree with 2-space, 4-space or tab indentation. Invalid JSON shows the exact line of the parse error. 🆔 Generate UUIDs in bulk Generate UUID v4 or v1 in batches of up to 100, copy them as a list or export them to a file. A random UUID generator for creating test data. 🔗 Decode URLs and read every parameter A URL decoder for percent-encoded URLs and query strings, with a table of already-parsed parameters to read every value at a glance. #️⃣ SHA-256, SHA-1 and MD5 hashes Compute SHA-256, SHA-1 and MD5 hashes of any text with the browser’s native Web Crypto engine. ⏱️ Convert Unix timestamps and epochs A Unix timestamp converter that turns an epoch value into ISO 8601, UTC, local time and a readable relative view, in seconds or milliseconds. 🎨 Convert HEX, RGB, HSL and OKLCH colors A color converter between HEX, RGB, HSL and OKLCH with a live preview swatch and a ramp of tints and shades. 📝 Lorem Ipsum placeholder text Placeholder paragraphs of Lorem Ipsum with a live word count. 🔒 Private by design No account, no sign-in, no telemetry. Hashing uses the native Web Crypto API and UUIDs use the browser’s own generator, so nothing you paste is ever transmitted. What runs in your browser stays in your browser. 👩‍💻 Made for developers Ideal for backend and frontend engineers, DevOps, QA and API integrators who work every day with JSON Web Tokens, encoded secrets, JSON responses and test data — and who would rather right-click than open five separate tools.