Cereio

Base64 Encoder/Decoder

Plain Text Input

0 characters

Base64 Output

No encoding result

Enter some text to see the encoded result here.

About Base64 Encoder/Decoder

Our free online Base64 Encoder and Decoder helps you convert text to Base64 encoding and decode Base64 strings back to plain text. Essential for working with data URIs, email attachments, API payloads, and any scenario where binary data needs to be represented as text.

Key Features

Encode & Decode

Convert text to Base64 or decode Base64 back to text.

Real-time Processing

See results instantly as you type.

UTF-8 Support

Properly handles Unicode characters and special symbols.

100% Client-side

All encoding/decoding happens in your browser - your data stays private.

Copy & Download

One-click copy or download results as a file.

Large Text Support

Handle large amounts of text efficiently.

How to Use

  1. 1Choose 'Encode' to convert text to Base64, or 'Decode' for the reverse.
  2. 2Enter or paste your text in the input area.
  3. 3The result appears instantly in the output area.
  4. 4Copy the result or download it as a file.

Pro Tips

  • 💡Base64 increases data size by ~33% - keep this in mind for large files.
  • 💡Data URIs use Base64: data:image/png;base64,iVBORw0...
  • 💡Base64 is encoding, not encryption - don't use it for security.
  • 💡URL-safe Base64 replaces + with - and / with _ for use in URLs.

Frequently Asked Questions

What is Base64?
Base64 is an encoding scheme that converts binary data into ASCII text using 64 characters (A-Z, a-z, 0-9, +, /). It's used when binary data needs to be stored or transmitted as text.
Is Base64 secure?
No! Base64 is encoding, not encryption. Anyone can decode Base64 data. Never use it to protect sensitive information.
Why does Base64 make data larger?
Base64 uses 4 characters to represent every 3 bytes of data, resulting in approximately 33% size increase. This tradeoff enables binary data to be transmitted as text.
What's URL-safe Base64?
Standard Base64 uses + and / which have special meanings in URLs. URL-safe Base64 replaces these with - and _ to avoid encoding issues.