Free

Developer Tools

JSON formatter, Base64 encoder, JWT decoder, hash generator, diff checker, timestamp converter & more.

Your files never leave your device
10:00 remaining
1
2
3
4
5
6
7
8
9
10

Related Tools

Unlock Limits

Get unlimited access to all tools and premium features to supercharge your workflow.

Upgrade to Pro

What is Developer Tools?

StackPro's Free Developer Tools is a collection of essential utilities every developer needs on a daily basis. Format and validate JSON, encode and decode Base64, inspect JWTs, generate hashes, compare text diffs, and convert timestamps — all from a single tab. Every tool processes data entirely in your browser, making it safe for sensitive data like API keys and authentication tokens.

How to Use Developer Tools

  1. Select the developer tool you need from the tab navigation.
  2. Paste or type your input data (JSON, Base64, JWT, text, etc.).
  3. Click the action button or see results instantly in real-time.
  4. Copy the output to your clipboard with one click.

Features

  • JSON formatter with syntax validation and error highlighting
  • Base64 encoder/decoder for strings and files
  • JWT decoder with header, payload, and signature breakdown
  • Hash generator supporting MD5, SHA-1, SHA-256, SHA-512
  • Text diff checker with side-by-side comparison
  • Unix timestamp converter to human-readable dates
  • URL encoder/decoder
  • 100% browser-based — safe for sensitive data

Frequently Asked Questions

What developer tools are included?▼
The suite includes a JSON formatter/validator, Base64 encoder/decoder, JWT (JSON Web Token) decoder, hash generator (MD5, SHA-1, SHA-256), text diff checker, timestamp converter, URL encoder/decoder, and more.
Is the JWT decoder secure?▼
Yes! The JWT decoder runs entirely in your browser. Your tokens are never sent to any server. This is critical for security since JWTs often contain sensitive authentication data.
Can I format and validate JSON?▼
Yes, the JSON formatter beautifies messy JSON with proper indentation, validates syntax, highlights errors with line numbers, and supports minification. You can also collapse/expand nested objects.
Do these tools work offline?▼
Yes! Since all processing happens client-side in your browser, the developer tools work even without an internet connection after the initial page load.