Free Online Developer Tools
Essential utilities for developers. Fast, secure, and privacy-focused. All processing happens in your browser—your data never leaves your device.
Browse All ToolsFeatured Tools
JSON / YAML / TOML Converter
Convert between JSON, YAML, and TOML formats instantly. Free online converter with automatic format detection and validation.
JWT Decoder
Decode and inspect JSON Web Tokens (JWT) instantly. View header, payload, and signature without verification. Free online JWT decoder.
Cron Expression Visualizer
Visualize and understand cron expressions. See next run times, get human-readable descriptions, and validate cron syntax.
Regex Playground
Test and debug regular expressions online. Interactive regex tester with syntax highlighting, match visualization, and capture groups.
UUID Generator
Generate random UUID v4 identifiers instantly. Bulk generate UUIDs with options for uppercase and hyphen-free formats.
Hash Generator
Generate SHA-256, SHA-384, and SHA-512 hashes instantly. Secure hash calculator for text and data verification.
Privacy First
All tools run entirely in your browser. No data is sent to servers.
Lightning Fast
No server round-trips. Instant results with minimal JavaScript.
Developer Friendly
Clean interfaces, keyboard shortcuts, and helpful error messages.