Developer Tools
Encode, decode, convert and debug — fast dev utilities.
11 free tools · updated regularly
PX to REM Converter
Convert pixels to rem and rem to pixels with a custom root font size — for responsive, accessible CSS.
Open tool →HTML Minifier
Compress HTML by removing comments and extra whitespace between tags — with size savings.
Open tool →String Escape / Unescape
Escape text for JSON and JavaScript strings (quotes, newlines, tabs) and reverse it.
Open tool →Diff Checker
Compare two blocks of text line by line and see exactly what was added and removed.
Open tool →Markdown Preview
Write Markdown and see the formatted HTML render live, side by side.
Open tool →Unix Timestamp Converter
Convert epoch time to dates and dates to timestamps, with a live current Unix timestamp.
Open tool →JWT Decoder
Decode a JSON Web Token's header and payload, view claims, and check expiry — privately.
Open tool →Number Base Converter
Convert between binary, octal, decimal and hexadecimal instantly — see all four at once.
Open tool →HTML Entities Encoder & Decoder
Convert special characters to HTML entities and back instantly — escape <, >, &, and quotes.
Open tool →URL Encode & Decode
Percent-encode text for safe use in URLs and decode encoded URLs back to readable text.
Open tool →Base64 Encode & Decode
Convert text to Base64 and decode Base64 back to text instantly, with full UTF-8 support.
Open tool →About Developer Tools
Essential developer utilities — Base64 and URL encoders, JWT decoder, number base converter, HTML entities, timestamp tools and more. All run client-side, so your data stays private.