Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 back to text instantly.
What is Base64 Encoding?
Base64 is a binary-to-text encoding scheme that represents binary data using 64 ASCII characters (A-Z, a-z, 0-9, +, /). It's used to transmit binary data over text-based protocols like email (MIME), embed images in HTML/CSS (data URIs), and encode credentials in HTTP Basic Authentication. Base64 increases data size by approximately 33%.
Common Use Cases
- •Encoding images for inline use in HTML/CSS data URIs
- •Decoding Base64 strings from API responses
- •Encoding binary data for JSON payloads
- •Working with HTTP Basic Authentication credentials
- •Embedding fonts or small files in stylesheets
Frequently Asked Questions
Is Base64 encryption?
No. Base64 is an encoding, not encryption. Anyone can decode Base64 without a key. It's designed for data transport, not security. Never use Base64 to protect sensitive information.
Why does Base64 increase data size?
Base64 represents every 3 bytes of input as 4 ASCII characters, resulting in a ~33% size increase. This overhead is the trade-off for being able to transmit binary data as plain text.
What is Base64URL?
Base64URL replaces + with - and / with _ to make the output safe for URLs and filenames. JWTs use Base64URL encoding. Standard Base64 characters + and / have special meanings in URLs.