JSON Formatter & Validator
Readable JSON, precise validation. Your numbers stay intact.
Open toolDeveloper tools
Format JSON, encode Base64 or URLs, generate UUIDs, calculate SHA-256 and prepare favicons. Check public websites and colour contrast with explicit limits.
Available tools
11 ToolsStructured data
Encoding, IDs & checksums
Base64 Encoder / Decoder
Encode Unicode text or decode Base64 back into readable text.
Open toolURL Encoder / Decoder
Encode a URL component or work with a complete URL.
Open toolUUID Generator
Generate cryptographically random version 4 UUIDs.
Open toolSHA-256 Hash Generator
Get a SHA-256 fingerprint of your exact UTF-8 text.
Open toolCompare File Checksums
Calculate a file’s SHA-256 checksum. Compare two files or check a trusted expected hash locally, without uploading their contents.
Open toolWebsites & web assets
Favicon Package Generator
Make a real ICO file, PNG icons, web manifest and installation snippet from one image. Review small icon sizes and download one checked ZIP.
Open toolWebsite, DNS & TLS Check
Inspect public HTTP response status, selected DNS records and TLS certificate checks from the website's server.
Open toolColour Contrast Checker
Check text and background colours against WCAG 2.2 contrast thresholds. See a live preview and copy the CSS colours.
Open tool