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44 tools · local-first

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JSON Formatter & Validator

Format, validate and minify JSON with precise error positions
Unix Timestamp Converter
Text Diff Checker
Regex Tester
JWT Decoder
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JSON & Data · 7
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 JSON to CSV, or parse CSV back into typed JSON objects
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
XML ↔ JSON Converter Convert XML documents to JSON and back, attributes included
JSON Schema Validator & Generator Validate JSON against a schema, or infer a schema from sample data
Encoding · 8
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
String Escaper / Unescaper Escape or unescape strings for JSON, JavaScript, Java, XML, SQL and CSV
Number Base Converter Convert numbers between binary, octal, decimal, hex and any base up to 36
Text ↔ Hex / Binary Converter Turn text into hex, binary or decimal bytes and decode byte dumps back
Image · 5
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
QR Code Decoder Read QR codes from images or live camera — URLs, WiFi and text, offline
Date & Time · 2
Unix Timestamp Converter Convert unix timestamps to human dates and back, with relative time
Cron Expression Parser Explain any cron schedule in plain English with the next run times
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
UUID Generator Generate UUID v4/v7, ULID and Nano ID — single or in bulk
Password Generator Random passwords with charset options and an honest entropy meter
QR Code Generator Generate crisp QR codes as SVG or PNG — no watermark, no upload
Hashing & Crypto · 2
Hash Generator MD5, SHA-1, SHA-256, SHA-512 and HMAC — computed in your browser
Bcrypt Hash & Verify Hash passwords with bcrypt and check hashes against plaintext
Code & Markup · 6
SQL Formatter Format SQL with dialect-aware keywords, or minify it to one line
XML Formatter & Validator Pretty-print, minify and validate XML with exact error positions
Markdown ↔ HTML Converter Render Markdown to HTML with live preview, or turn HTML back into Markdown
HTML Formatter & Minifier Beautify messy HTML or minify it for production
CSS Formatter & Minifier Beautify CSS for reading or minify it for shipping
JavaScript Formatter & Minifier Beautify JavaScript or minify it with real compression and mangling
Privacy · 1
EXIF Viewer & Remover See what metadata your photos carry — and strip it without re-encoding