Base64 Encoder/Decoder - Free Online Tool

How to Use Base64 Encoder/Decoder

1

Choose Encode or Decode using the toggle at the top.

2

Paste or type your text or Base64 string into the Input area.

3

Click the action button to encode or decode the content.

4

Review the result in the Output panel on the right.

5

Use the Copy button to place the output on your clipboard.

6

Optionally swap input and output if you want to reverse the operation.

Key Features & Security

Instant Base64 encode and decode operations.

Copy and swap shortcuts to speed up repeated conversions.

Monospace displays for easier inspection of long strings.

Local processing so secrets and tokens stay on your device.

No sign-up or backend requests required.

Frequently Asked Questions

What does the Base64 Encoder/Decoder tool do?

The tool converts plain text into Base64-encoded text and decodes Base64 strings back to their original form. It is handy when working with APIs, data URIs or debugging encoded payloads.

Is the utoolsy Base64 tool secure?

Yes. Encoding and decoding happen entirely in your browser, so any secrets, tokens or private content you paste are not sent to utoolsy servers.

Why do I sometimes see an error when decoding?

Decoding requires a valid Base64 string. If characters are missing, corrupted or not Base64 at all, the tool will show an error message rather than returning incorrect text.

Can I use this for binary data?

The interface is optimised for text. For binary files, convert them to Base64 elsewhere and then paste the string if you only need to inspect or decode the textual representation.