Developer Tools · Free Online Toolbox
Free, must-have tools for developers: JSON formatting, Base64, URL encoding, regex testing, hashing, JWT decoding, Cron, and more.
Port Lookup
Image Compressor
QR Code Generator
JSON Formatter
Color Picker
Base64 Encoder/Decoder
URL Encoder / Decoder
Hash Generator
UUID Generator
Image to Base64
Timestamp Converter
Regex Tester
Base Converter
Password Generator
Password Strength Checker
CSS Minifier
JSON Minifier
HTML Minifier
Markdown to HTML
CSV to JSON
JSON to CSV
JWT Decoder
Cron Expression Generator
HTTP Status Codes
Random Number Generator
HTML Encoder / Decoder
Color Converter
URL Parser
SQL Formatter
XML Formatter
YAML to JSON Converter
CSS Formatter
JSON Validator
JSON to YAML Converter
HTML to Markdown Converter
Color Contrast Checker
User Agent Parser
JWT Encoder
XML to JSON Converter
Image Resizer
Color Palette Generator
Image Rotate & Flip
Image Cropper
CSV to Markdown Table
Base64 to Image
Why choose FreeToolset's developer tools?
FreeToolset offers dozens of free online developer tools covering the everyday needs of frontend work, backend debugging, and data processing. Every tool runs locally in your browser, so your code and data are never uploaded to any server — which matters when handling sensitive information such as API keys, JWT tokens, or private configs.
No need to install Node.js, Python, or any IDE plugin — just open your browser and go. The tools work on both desktop and mobile, so you can format a JSON response or generate a UUID on your commute. We keep adding tools; recently we added the Color Converter, URL Parser, SQL Formatter, XML Formatter, YAML to JSON, CSS Formatter, and JSON Validator.
Developer Tools FAQ
- Are these developer tools really free?
- Yes. All 95+ tools on FreeToolset are completely free to use — no account required, no feature limits, and no ads.
- Is my code data safe? Is it uploaded to a server?
- Absolutely safe. All processing happens in your browser; your code and data never leave your device. Most tools keep working even offline.
- Which languages can I format?
- We currently support formatting and minification for JSON, XML, YAML, SQL, CSS, HTML, and JavaScript, plus Markdown ↔ HTML conversion. CSV and JSON can also be converted to each other.
- Can I use them on my phone?
- Yes. Our tools are responsive and work smoothly in mobile browsers — handy for quickly inspecting a JWT or formatting JSON on the go.
- How do I bookmark my favorite tools?
- Simply bookmark the tool's page in your browser. Each tool has its own URL, making it easy to share with teammates.
📚 Further Reading
Want to go deeper? These tutorials pair well with this tool.
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