Base64 Encode & Decode Online Free
Encode plain text to Base64 or decode Base64 back to text instantly in your browser. Free, no signup, no data sent to any server.
How to Encode or Decode Base64
- 1
Choose Encode or Decode
Select the "Encode" tab to convert plain text to Base64, or the "Decode" tab to convert Base64 back to plain text.
- 2
Paste your input
Type or paste your text into the input box. The result updates live as you type.
- 3
Copy the result
Click "Copy" to copy the output to your clipboard.
Base64 encodes binary data as a string of 64 printable ASCII characters (A–Z, a–z, 0–9, +, /). Every 3 bytes of input become 4 Base64 characters, so encoded output is roughly 33% larger than the original. Padding characters (=) are added at the end if the input length is not a multiple of 3.
Common uses: Embedding images directly in HTML or CSS as data URLs (data:image/png;base64,…), encoding credentials in HTTP Basic Authentication headers, encoding binary data in JSON payloads, and storing binary blobs in XML or email attachments (MIME).
Unicode note: The browser's native btoa() only handles Latin-1 characters. This tool converts your text through UTF-8 first, so emoji, Chinese, Arabic, and all Unicode characters encode and decode correctly.