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Format, validate and prettify JSON data
Encode and decode Base64 strings
Encode and decode URL components
Decode and inspect JWT tokens
Test REST APIs directly in your browser
Parse, extract, and analyze URL components
Convert between HEX, RGB, and HSL
Create beautiful CSS gradients visually
Live markdown rendering with preview
Generate favicons from text or emoji
Test and debug regular expressions
Compare texts and see differences
Convert text to URL-friendly slugs
Generate placeholder text easily
Convert text between different casing styles
Count words, characters, and sentences
Generate random UUID v4 identifiers
Unix timestamp and date conversion
SHA-256 / SHA-512 text hashing
Generate secure, random passwords
Git, Docker, Linux, JavaScript, Python, SQL and more.
Common questions about DeveloperLeap tools and privacy.
Browse all developer utilities in one place.