10 Free Developer Tools You Didn't Know You Needed

As developers, we spend a surprising amount of time on small utility tasks: formatting JSON, testing regex patterns, converting timestamps, generating UUIDs, encoding Base64 strings. Each task takes only a minute, but they add up. Here are 10 free tools on Kitmul that handle these tasks instantly — no installs, no accounts, no nonsense.

1. JSON Formatter & Validator — Paste messy JSON, get clean, syntax-highlighted output with validation errors highlighted. 2. Regex Tester — Write and test regular expressions with real-time matching, group highlighting, and common pattern templates. 3. UUID Generator — Generate v4 UUIDs in bulk with one click. Copy-paste ready. 4. Base64 Encoder/Decoder — Convert text or files to and from Base64 instantly. 5. Unix Timestamp Converter — Convert between Unix timestamps and human-readable dates across time zones.

6. Color Converter — Switch between HEX, RGB, HSL, and other color formats with a live preview. 7. JWT Decoder — Paste a JWT token and see the decoded header, payload, and signature. No server involved. 8. Markdown Preview — Write Markdown and see a live preview side-by-side. 9. CSS Minifier — Minify your CSS with one click for production-ready output. 10. Hash Generator — Generate MD5, SHA-1, SHA-256, and other hashes from text or files.

All of these tools run entirely in your browser. Your code, tokens, and data never leave your device. Bookmark kitmul.com/en/developer and save yourself hours every week.