Base64 Converter
Easily encode text to Base64 format or decode Base64 strings back to text. All processing happens in your browser.
What is Base64 Encoding?
Base64 is a group of binary-to-text encoding schemes that represent binary data in an ASCII string format by translating it into a radix-64 representation. The term Base64 originates from a specific MIME content transfer encoding.
It is designed to carry data stored in binary formats across channels that only reliably support text content. Base64 is particularly common in contexts like:
- Email attachments (MIME) due to historical 7-bit ASCII limitations.
- Embedding small images directly into HTML or CSS (Data URIs).
- Storing complex data in URLs or cookies.
How Base64 Works
Base64 operates by dividing binary data into 6-bit chunks. Each 6-bit chunk has a value between 0 and 63, which maps to a character in the Base64 alphabet:
If the total number of bytes is not divisible by 3 (so the bits aren't divisible by 6), the output is padded with = characters to align the final chunk.
Common Uses
Data URIs
Displaying images without a separate HTTP request:<img src="data:image/png;base64,iVBOR..." />
Basic Auth
Encoding credentials in HTTP headers:Authorization: Basic dXNlcm5hbWU6cGFzc3dvcmQ=