Tools
Base64 encoder & decoder
Encode plain text to Base64 or decode Base64 back to UTF-8. Everything runs in your browser.
FAQ
Why not use btoa/atob directly for Unicode?
btoa only accepts binary strings in the Latin-1 range. This tool encodes your text as UTF-8 bytes first, then Base64, so emoji and all Unicode work correctly.
How does auto-detect work?
After removing whitespace, if the string length is a multiple of four and only contains Base64 alphabet characters with valid padding, we suggest decoding. It is a hint only; invalid payloads still show an error when you decode.
Is my data sent to a server?
No. Encoding and decoding happen entirely in your tab using the Web APIs above.