Base64 Encode / Decode

Encode UTF-8 text into Base64 format or decode Base64 encoded strings back to plain text online.

How to use this calculator

1. Select encode or decode.
2. Paste string.
3. Copy output.

Formula & method

RFC 4648 Base64 Scheme

6-bit Chunks → ASCII Chars

Standard web encoding.

Example

Hello World! -> SGVsbG8gV29ybGQh.

Key insights

• Base64 increases size by ~33%.

How to interpret your result

Base64 Output

ASCII representation of data.

Frequently asked questions

Is Base64 encryption?

No, it is encoding.

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