Developer Tools
JSON formatter, encoders and dev utilities
Regex Tester
Test regular expressions live with highlighted matches
Developer ToolsBase64 Encoder & Decoder
Encode and decode Base64 with full Unicode support
Developer ToolsTimestamp Converter
Convert Unix timestamps to dates and dates to timestamps, instantly.
Developer ToolsJSON Formatter
Validate, format, beautify and minify JSON instantly
Developer ToolsJWT Decoder
Decode JSON Web Tokens and inspect their claims.
Developer ToolsHash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes instantly.
Developer ToolsURL Encoder & Decoder
Encode and decode URLs and query strings instantly.
Developer ToolsJSON to CSV Converter
Convert JSON arrays to CSV spreadsheets instantly.
Developer ToolsCSV to JSON Converter
Convert CSV spreadsheets to clean JSON instantly.
Developer ToolsUUID Generator
Generate cryptographically secure UUID v4 IDs
Developer ToolsColor Picker
Pick colors and convert HEX, RGB and HSL instantly
Developer ToolsPassword Strength Checker
Test password strength with entropy scoring
Developer ToolsColor Converter
Convert colors between HEX, RGB, HSL, and CMYK.
Developer ToolsCSS Minifier
Minify CSS for faster-loading websites.
Developer ToolsHTTP Status Codes
Look up every HTTP status code with plain-English meanings.
Developer ToolsJSON Validator
Validate JSON with friendly error messages
Developer ToolsQR Code Scanner
Decode QR codes from images or camera
Developer ToolsMarkdown Preview
Write Markdown and watch it render live, side by side
Developer ToolsYouTube Thumbnail Viewer
Preview every YouTube thumbnail size
Developer ToolsMeta Tag Generator
Generate SEO meta tags in seconds
Developer ToolsJavaScript Minifier
Shrink JS by stripping comments and whitespace
Developer ToolsOpen Graph Generator
Social preview cards for your links
Developer ToolsJSON Minifier
Compress JSON to its smallest size
Developer ToolsURL Parser
Break any URL into its parts
Developer ToolsSitemap Generator
Generate XML sitemaps from a URL list
Developer ToolsContrast Checker
WCAG contrast ratios for text readability
Developer ToolsHTML Previewer
Preview HTML instantly in a sandbox
Developer ToolsHTML Minifier
Compress HTML for faster page loads
Developer ToolsRobots.txt Generator
Build a correct robots.txt visually
Developer ToolsHTML Encoder Decoder
Encode and decode HTML entities
Developer ToolsRandom Color Generator
Random color palettes with lockable swatches
Developer ToolsXML Formatter
Pretty-print XML with clean indentation
Developer ToolsUser Agent Parser
Decode any browser user agent string
Developer ToolsColor Shades Generator
Tints and shades from any base color
Developer ToolsAbout our free developer tools
JoliTools developer utilities are built for speed. Format and validate JSON, encode and decode Base64 and URLs, and convert colors, all with keyboard-friendly interfaces that respect your flow.
Like every JoliTools utility, these run 100% client-side. Paste API responses and tokens without worrying about your data leaving the machine.