About DevToolBox
DevToolBox is a free, privacy-first collection of utilities for software developers. Every tool runs entirely in your browser — nothing is uploaded to a server, nothing is logged, and nothing is stored beyond the lifetime of the page.
Our mission
Most developers reach for the same handful of helpers many times a day: format a JSON response, decode a JWT, generate a UUID, look up an HTTP status code, work out a colour contrast ratio. DevToolBox brings those everyday utilities into one fast, ad-supported, sign-up-free site so you can stay in flow instead of digging through bookmarks.
What's inside
- JSON Formatter — format, minify, validate, and explore JSON with a tree view
- Regex Tester — test regular expressions with real-time match highlighting
- Base64 Encode / Decode — convert text to Base64 and back, with full Unicode support
- URL Encoder / Decoder — encode and decode URLs and query-string parameters
- JWT Decoder — inspect the header and payload of a JSON Web Token
- Timestamp Converter — convert between Unix timestamps and human-readable dates
- Color Converter — translate HEX, RGB, and HSL with a live swatch and WCAG contrast check
- Number Base Converter — flip between binary, octal, decimal, and hexadecimal
- Case Converter — switch text between camelCase, snake_case, kebab-case, and more
- JSON ↔ YAML — convert configuration between JSON and YAML in one click
- UUID Generator — produce RFC 4122 v4 UUIDs in bulk
- Hash Generator — compute MD5, SHA-1, SHA-256, SHA-384, and SHA-512 of any text
- QR Code Generator — turn URLs or text into a scannable QR code
- Cron Expression Parser — translate a crontab line into plain English and preview next runs
- HTTP Status Codes — searchable reference with the meaning of every code
Contact
Suggestions, bug reports, or partnerships? Email us at contact@zhujiuyin.com. We read every message.