Base64 Decoder
Reverse Conversion
How This Converter Works
Validates standard-alphabet Base64 and decodes the bytes as strict UTF-8 text. Unambiguous inputs with omitted terminal padding are accepted.
Formula or rule
Restore omitted terminal padding when the input length modulo 4 is 2 or 3, then Base64-decode and UTF-8-decode. Invalid Base64 or UTF-8 is rejected.
Example
- Input
- SGVsbG8=
- Calculation
- Decode the Base64 bytes and interpret them as UTF-8.
- Result
- Hello