Base64 Encode/Decode Tool

Base64 Encoding Introduction

What is Base64?

Base64 is an encoding scheme that converts binary data into printable ASCII characters using 64 characters (A-Z, a-z, 0-9, +, /) with padding character '=' to ensure the output length is always a multiple of 4. Widely used in scenarios requiring text-based binary data transmission like email attachments, JSON data exchange, and embedded images.

How It Works

  • Split original data into 3-byte (24-bit) chunks
  • Map each 6-bit chunk to corresponding Base64 characters
  • Use '=' padding when input length isn't multiple of 3
  • Final encoding process includes binary conversion and character mapping

Key Advantages & Applications

Advantages:
  • Secure binary data transmission in text environments
  • Cross-platform compatibility
  • Simple and efficient implementation
Common Applications:
  • Email attachments (MIME encoding)
  • Data URI embedding in web development
  • HTTP Basic Authentication
  • Data signature & verification

Important Notes

  • Encoded data size increases by ~33%, not suitable for large data
  • Base64 is encoding NOT encryption
  • Implementation variations in line breaks and padding

Frequently Asked Questions

1. Why use Base64 encoding?

Enables binary data transmission in text-only environments like emails and JSON, ensuring data integrity.

2. Does Base64 provide security?

No, it's only encoding. Encoded data can be easily decoded, not suitable for sensitive information.

3. Why does encoded data size increase?

Converts 3 bytes to 4 characters (6 bits each), resulting in ~33% size increase.

4. Typical use cases?

Email attachments, embedded images in HTML, HTTP Auth, and text-based binary transmission.

5. How to handle padding characters?

Use '=' padding when input length isn't multiple of 3. Different implementations may vary slightly.