What is Base64 Encode / Decode?
Translates binary or UTF-8 text into a 64-character ASCII representation (A-Z, a-z, 0-9, +, /) for safe transmission across email and web protocols.
How to Use This Calculator
- Select Encode or Decode mode.
- Enter text or Base64 string.
- Copy converted output.
The Mathematical Formula & Variables
Splits every 3 bytes (24 bits) into 4 6-bit Base64 index values
Step-by-Step Worked Example
Scenario: Encoding "CalculatorSee".
- Converts ASCII characters into 8-bit bytes.
- Groups into 6-bit chunks.
- Maps to Base64 index table.
Result: Q2FsY3VsYXRvcmlvbg==
Frequently Asked Questions
Why does Base64 make files ~33% larger?
Base64 represents 3 bytes of binary data using 4 ASCII characters, resulting in a 4/3 (approx 133%) size expansion.