Free Encoding & Transformation Tools

Encode, decode, hash, and transform data with free online tools. Base64, URL encoding, MD5/SHA hashing, JWT decoding, HTML entity encoding — all processed locally in your browser.

Secure, Local Encoding

Encoding and hashing are fundamental operations in web development, security, and data processing. But processing sensitive data through online tools raises privacy concerns. Our encoding tools process everything locally in your browser — your data never leaves your device, never hits our servers, and is never stored or logged.

This is especially important when working with JWT tokens (which contain authentication data), API keys, or proprietary information. You can use these tools with confidence that your data stays private.

Available Encoding Tools

Base64 Encoder/Decoder

The most versatile encoding tool. Encode text to Base64 and decode Base64 back to plain text. Supports UTF-8 handling, file content, and handles binary-safe encoding. Used for data URIs, email MIME attachments, JWT decoding, and API authentication headers. One-click copy of encoded/decoded output.

URL Encoder/Decoder

Convert special characters to URL-safe percent-encoding and decode them back. Essential when building URLs with query parameters that contain spaces, symbols, or non-ASCII characters. Handles the full RFC 3986 specification for URI encoding.

MD5 Hash Generator

Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from any text input or file upload. See the hash in hexadecimal and Base64 formats. Useful for file integrity verification, checksum generation, and data fingerprinting. Note: MD5 and SHA-1 are not suitable for security-critical applications.

JWT Decoder

Decode JSON Web Tokens to inspect their contents. Splits the token into header, payload, and signature components, decodes the Base64-encoded sections, and displays claims in a readable format. All decoding happens locally — your tokens are never sent to a server.

HTML Entity Encoder/Decoder

Encode special HTML characters (like <, >, &, ") into their entity equivalents (<, >, &, ") and decode them back. Essential for safely displaying user-generated content in web pages and preventing XSS vulnerabilities.

Encoding Best Practices

Use URL encoding for all query parameters. If your URL contains user input, spaces, or special characters — encode them. Browsers handle some encoding automatically, but explicit encoding prevents bugs and security issues.

Never store passwords as MD5 or SHA-1 hashes. These algorithms are cryptographically broken and vulnerable to collision attacks. Use SHA-256 or stronger for any security application. Bcrypt and Argon2 are recommended for password storage.

Verify JWT signatures on your server. The JWT Decoder shows claims but doesn't verify signatures. Always validate JWT integrity server-side using your secret or public key.