31 tools · local-first
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JSON & Data · 5
JSON Formatter & Validator Format, validate and minify JSON with precise error positions JSON ↔ YAML ↔ TOML Converter Convert between JSON, YAML and TOML with format auto-detection JSON → CSV Converter Flatten arrays of JSON objects into CSV with proper escaping JSON → TypeScript Types Infer TypeScript interfaces from a JSON sample instantly JSONPath Tester Query JSON with JSONPath expressions and see every match with its path
Encoding · 5
Base64 Encode / Decode Encode text to Base64 or decode Base64 to text, URL-safe included JWT Decoder Decode JWT header and payload, check expiry — fully offline URL Encode / Decode Percent-encode or decode URL components and query strings HTML Entities Encode / Decode Escape text for HTML or decode &-style entities back to characters Unicode Character Inspector See code points, UTF-8/UTF-16 bytes and escapes for every character
Image · 4
Image ↔ Base64 Converter Turn images into Base64 data URLs and back — with CSS and HTML snippets Image Format Converter Convert images between PNG, JPEG and WebP with a quality dial Image Resizer Resize images by width, height or percentage — sharp and entirely offline Favicon Generator Turn any image into favicon.ico plus the full PNG and manifest icon set
Date & Time · 2
Web · 4
Regex Tester Test regular expressions with live match highlighting and groups URL Parser Break a URL into protocol, host, path and query parameters Color Converter Convert colors between HEX, RGB, HSL and OKLCH with live preview User-Agent Parser Identify browser, engine, OS and device from a User-Agent string
Text · 6
Text Diff Checker Compare two texts line by line and see additions and deletions Case Converter Switch between camelCase, snake_case, kebab-case, PascalCase and more Word Counter Count words, characters, sentences, bytes and reading time as you type Lorem Ipsum Generator Generate placeholder words, sentences or paragraphs for mockups Slug Generator Turn titles into clean URL slugs with separator and length options Sort & Dedupe Lines Sort lines alphabetically or naturally, remove duplicates and empties
Generators · 3
Hashing & Crypto · 2