Developer Tools calculators
Base64, URL encoding, JSON, hashes, UUIDs, colors and number bases.
29 free tools
Most used
Base64 Encode / DecodeConvert text to Base64 and back instantly, with full UTF-8 and URL-safe supportColor Converter (HEX to RGB)Convert any color between HEX, RGB, HSL, HSV and CMYK in one stepHash GeneratorGenerate MD5, SHA-1, SHA-256 and SHA-512 hashes and verify checksumsIP Subnet CalculatorFind network, broadcast, host range and mask for any IPv4 address and CIDRJSON Formatter & ValidatorBeautify, minify and validate JSON with the exact line and column of any errorNumber Base ConverterConvert between binary, octal, decimal, hex and any base from 2 to 36QR Code GeneratorMake a free QR code for a link, Wi-Fi network, text, email or phoneRegex TesterTest JavaScript regular expressions live, with matches, groups and replaceUnix Timestamp ConverterConvert Unix epoch time to a readable date and any date back to epochURL Encode / DecodePercent-encode or decode URLs, query strings and form data correctlyUUID GeneratorCreate random v4 or time-ordered v7 UUIDs in bulk, and validate any UUID
More developer tools tools
Aspect Ratio CalculatorFind any aspect ratio and resize width or height without distortionBarcode GeneratorMake scannable UPC, EAN, Code 128 and Code 39 barcodes — download as SVG or PNGChmod CalculatorConvert Linux file permissions between 755, rwxr-xr-x and checkboxesColor Contrast CheckerTest text and background colours against WCAG AA and AAA in secondsCron Expression ParserTranslate any crontab schedule into plain English and see its next runsCSS Gradient GeneratorDesign linear, radial and conic gradients and copy clean CSSCSV to JSON ConverterPaste CSV, get clean JSON — headers, quotes and types handledDownload Time CalculatorSee how long any file takes to download or upload at your internet speedHTML Entity Encoder / DecoderEscape text to HTML entities or decode &, © and © back to textJSON to CSV ConverterTurn a JSON array into a spreadsheet-ready CSV with nested keys flattenedJWT DecoderDecode a JSON Web Token and check when it was issued and expiresMarkdown to HTML ConverterConvert Markdown to clean, semantic HTML you can paste anywherePX to REM ConverterConvert CSS pixels to rem and back — single values or whole stylesheetsText to Binary ConverterTranslate text to binary, hex, decimal or octal — and decode it backURL Slug GeneratorTurn any title into a clean, SEO-friendly URL slugYAML to JSON ConverterConvert YAML to JSON and JSON to YAML — and validate as you goPPI CalculatorFind pixel density, dot pitch and screen size from resolutionSQL FormatterBeautify messy SQL into clean, indented, readable queries