Free Online Base64 Encoder and Decoder

Encode and decode Base64 strings directly in your browser. No upload, no signup — your data stays on your device, 100% private and secure.

All processing is done locally in your browser. Your data never leaves your device.

How to Use Base64 Encode/Decode

Enter your text in the input field, or upload a file to encode/decode.
Click "Encode" to convert text to Base64, or use the parameter options to switch encoding.
Copy the result to your clipboard or download it as a text file.
Supports UTF-8 and GBK encodings for international text.

Key Features

100% client-side — your data never leaves your device
Supports both encoding and decoding
Multiple encoding options: UTF-8 and GBK
File upload support for batch processing
Copy to clipboard and download output
No signup, no installation, completely free

Frequently Asked Questions

What is Base64 encoding?

Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It is commonly used to encode data for transmission over text-based protocols like HTTP.

Is my data safe when using this tool?

Absolutely. All Base64 encoding and decoding happens entirely in your browser. Your data never leaves your device. No server-side processing occurs.

Can I decode Base64 strings?

Yes, this tool supports both encoding and decoding. Simply paste your Base64 string and the tool will decode it back to the original text.

What encodings are supported?

The tool supports UTF-8 and GBK encodings. UTF-8 is the default and works for most international text, while GBK is useful for legacy Chinese text.

Can I upload a file for Base64 conversion?

Yes, the tool supports file upload. You can upload a file and the tool will encode its contents to Base64.