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Encode / Decode Toolkit

Encode / Decode

Base64, URL encode, HTML entities, binary, hex, ASCII, Unicode escape, ROT13, Base32, and JWT decoder — all in one place.

#base64#url encode#html entities#binary#hex#ascii#unicode#rot13#base32#jwt

What's included in Encode / Decode Toolkit

10 tools, all free and client-side — no login or data upload required.

Base64 Encode / Decode

Encode plain text or binary data to Base64, or decode Base64 strings back to readable text — supports file encoding too.

  • Embed images as data URIs in HTML/CSS
  • Encode API credentials for HTTP Basic Auth
  • Decode Base64 payloads from API responses or emails

URL Encode / Decode

Percent-encode special characters in URLs for safe transmission, or decode URL-encoded query strings.

  • Encode query parameters with special characters
  • Decode URL-encoded form submissions
  • Debug percent-encoded URLs from server logs

HTML Entities

Convert characters like <, >, &, and " to HTML entities and vice versa for safe HTML embedding.

  • Safely embed user-generated content in HTML
  • Decode HTML entities from scraped web content
  • Prevent XSS by encoding special characters

Binary Converter

Convert any text string to its binary (0s and 1s) representation and decode binary back to text.

  • Visualize text as binary for educational purposes
  • Debug binary data protocols
  • Generate binary strings for computer science assignments

Hex Converter

Encode text as hexadecimal bytes and decode hex strings back to readable characters.

  • Inspect hex-encoded database values
  • Convert hex color codes to text
  • Debug hex-encoded network payloads

ASCII Converter

Convert text to ASCII decimal codes and decode ASCII code sequences back to their character equivalents.

  • Look up ASCII values for special characters
  • Debug character encoding issues
  • Generate ASCII art character mappings

Unicode Escape

Escape Unicode characters to \uXXXX sequences for use in JSON, JavaScript, and Java source code.

  • Safely include emoji and special chars in JSON
  • Escape Unicode for Java .properties files
  • Debug Unicode encoding in internationalized apps

ROT13 Cipher

Apply the ROT13 substitution cipher to text — useful for hiding spoilers and obfuscating content.

  • Hide spoilers in forum posts and emails
  • Encode answers in puzzle or quiz content
  • Apply basic obfuscation for non-sensitive text

Base32 Encode / Decode

Encode and decode data using the Base32 alphabet (RFC 4648) — used in TOTP, OTP, and some file formats.

  • Generate TOTP secret keys for two-factor authentication
  • Encode binary data for case-insensitive systems
  • Debug Base32-encoded tokens from authentication libraries

JWT Decoder

Decode any JSON Web Token and inspect its header algorithm, payload claims, and expiration without a secret key.

  • Inspect JWT claims during API debugging
  • Check token expiration without parsing code
  • Audit user roles and permissions encoded in JWTs