Base64 Encoder / Decoder
Developer ToolsEncode or decode Base64 from UTF-8 text.
Calculated Result
Base64
Formula: UTF-8 bytes ↔ RFC 4648
About this calculator
APIs and data URLs use Base64. Type plain text to encode, or a Base64 string to decode. UTF-8 is used so accented letters survive the round trip.
How It Works & Formula
FormulaUTF-8 bytes ↔ Base64 (RFC 4648)
TextEncoder makes UTF-8 bytes, then btoa. Decode reverses with atob and TextDecoder.