Developer
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Featured tools
Start with the core developer workflows
Developer Tools
JSON Formatter
Format, minify, and validate JSON text with friendly error messages.
Developer Tools
URL Encoder / Decoder
Encode or decode URL text safely for links, query strings, and web forms.
Developer Tools
UUID Generator
Generate one or multiple UUID v4 values and copy them easily.
Developer Tools
Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 back into readable text.
Developer Tools
QR Code Generator
Generate a QR code from text or a URL and download it as a PNG image.
Developer Tools
New
Regex Tester
Test regular expressions against sample text in your browser.
12 tools in this category
Developer Tools
URL Encoder / Decoder
Encode or decode URL text safely for links, query strings, and web forms.
Developer Tools
JSON Formatter
Format, minify, and validate JSON text with friendly error messages.
Developer Tools
UUID Generator
Generate one or multiple UUID v4 values and copy them easily.
Developer Tools
Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 back into readable text.
Developer Tools
New
Regex Tester
Test regular expressions against sample text in your browser.
Developer Tools
New
JWT Decoder
Decode JWT header and payload JSON without verifying the signature.
Developer Tools
New
SQL Formatter
Format SQL queries for easier reading and debugging.
Developer Tools
New
HTML Formatter
Format HTML snippets for readability.
Developer Tools
New
CSS Formatter
Format CSS snippets into readable blocks.
Developer Tools
New
Markdown Previewer
Preview basic Markdown text as readable formatted output.
Developer Tools
New
JSON Validator
Validate JSON syntax and show friendly parser feedback.
Developer Tools
New
CURL to Fetch Converter
Convert simple cURL commands into JavaScript fetch examples.
Featured developer guides
Productivity Guides
Best Free Online Tools for Daily Work
A useful roundup of browser-based tools for documents, images, text cleanup, passwords, calculations, and quick productivity tasks.
6 min read
Security Guides
Password Generator Guide: How to Create Strong Random Passwords
Learn what makes a password stronger, how to use a password generator, and why storage matters as much as password length.
5 min read
Text Guides
Word Counter Guide: When Word Count and Character Count Matter
Learn how word counters help with essays, social posts, meta descriptions, applications, and writing cleanup.
4 min read
About developer tools
Developer utilities are small but frequent tasks. Formatting JSON, decoding URLs, creating UUIDs, or converting Base64 text should be fast, readable, and easy to copy.
These tools are designed for snippets, examples, testing, support messages, and lightweight debugging. They do not replace full validation, security review, or production testing.
FreeToolKit is designed for fast, no-signup workflows on mobile and desktop. Use the search box above to filter this category, or open All Tools to browse the full directory of free AI and everyday productivity tools.
Helpful answers
Frequently asked questions
Can I format JSON online?
Yes. JSON Formatter validates, formats, and minifies JSON in the browser.
Are UUIDs secrets?
No. UUIDs are identifiers, not passwords or authentication tokens.
When should I encode a URL?
Encode URL parts when spaces or special characters need to be safely included in a link or query string.