JSON formatter, regex tester, JWT decoder, UUID generator, and more. All tools process data locally - your code never leaves your device.
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Instant Processing
Client-side processing means instant results with no server latency.
Works Offline
Once loaded, tools work without internet. Perfect for secure environments.
Everything you need for debugging, encoding, and data manipulation
JSON Formatter
Format, validate, and minify JSON with syntax highlighting
Debug API responses and config files
Regex Tester
Test regular expressions with real-time matching and capture groups
Build and test patterns for validation
JWT Decoder
Decode JWTs to view header, payload, and expiration
Debug authentication issues securely
UUID Generator
Generate UUID v4 identifiers in bulk
Create unique IDs for database records
Base64 Encoder
Encode and decode Base64 strings with UTF-8 support
Handle encoded data in APIs
Hash Generator
Generate MD5, SHA-256, SHA-512 hashes from text or files
Verify file integrity and create checksums
URL Encoder
Encode and decode URL components properly
Handle special characters in URLs
Timestamp Converter
Convert between Unix timestamps and human-readable dates
Debug time-related issues
Diff Checker
Compare two texts and see differences highlighted
Review code changes and config diffs
Cron Generator
Build cron expressions visually with next run preview
Schedule jobs correctly
Color Converter
Convert between HEX, RGB, HSL color formats
Work with colors in CSS
Markdown Preview
Write markdown and see live preview
Write documentation and READMEs
Common questions about free developer tools
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