Developer tools that stay in your browser

{ } JSON Formatter Format, minify and validate JSON. 64 Base64 Encode / Decode Text ↔ Base64, standard or URL-safe. JWT JWT Decoder Inspect header, payload and expiry. % URL Encode / Decode Percent-encode or decode URLs. ID UUID Generator Generate random UUID v4 identifiers. # Hash Generator SHA-1 / 256 / 384 / 512 of any text. ⏱ Timestamp Converter Unix epoch ↔ human date, any zone. Aa Text & Case Tools Count, transform case, slugify text. ◧ Color Converter HEX ↔ RGB ↔ HSL with preview. .* Regex Tester Test patterns, see matches and groups. \d+ Regex Builder Build regex from blocks & ready patterns. ⏲ Cron Explainer Read a cron line and its next runs. ± Text Diff Line-by-line diff of two texts. </> HTML Entities Encode or decode HTML entities. ¶ Lorem Ipsum Generate placeholder text. 0b Number Base Converter Bin / Oct / Dec / Hex, big numbers. 🔑 Password Generator Strong random passwords, crypto-grade. M↓ Markdown Preview Render Markdown to HTML live. 755 Chmod Calculator Unix permissions ↔ octal & symbolic. ?= Query String ↔ JSON Parse or build URL query strings. , CSV ↔ JSON Convert between CSV and JSON. aA Case Converter camelCase, snake_case, kebab-case… ◐ Contrast Checker WCAG contrast ratio & AA/AAA. ≡ Line Tools Sort, dedupe, reverse, shuffle lines. 🔗 URL Parser Break a URL into its components. U+ Unicode Inspector Code points, UTF-8 bytes, entities. TS JSON → TypeScript Infer TypeScript interfaces from JSON. \n String Escape Escape / unescape JS & JSON strings. Ⅳ Roman Numerals Integer ↔ Roman numeral. 01 Text ↔ Binary Text to 8-bit binary and back. 🖼 Image → Base64 Image to Base64 data URI, local. ⤓ cURL → fetch Turn a curl command into fetch(). $. JSON Path Query Extract values from JSON by path. ▚ QR Code Generator Text or URL to a QR code — PNG or SVG.