Base64 Encoder & Decoder
Encode and decode Base64 strings instantly. Supports Unicode. All processing happens in your browser—no data sent to any server.
Base64 to Decode
Decoded Text
Decoded text will appear here
What is Base64?
Base64 is a group of binary-to-text encoding schemes that represent binary data in an ASCII string format. It's widely used when you need to store or transfer binary data over media that only supports text—like embedding images in HTML or sending attachments in email.
How it works
- Encode: Converts your text into Base64 format using the standard A-Z, a-z, 0-9, +, / character set.
- Decode: Converts a valid Base64 string back to the original text.
- Unicode: Full support for international characters and emoji via UTF-8 encoding.
Frequently Asked Questions
What is Base64 encoding?
Is my data sent to a server?
Does this support Unicode and emoji?
When is Base64 used?
Is this Base64 tool free?
What is Base64 Decoding?
Base64 decoding is the reverse of Base64 encoding. It converts an ASCII string composed of 64 printable characters (A–Z, a–z, 0–9, +, /) back into the original binary or text data. Base64 is commonly used to transmit binary data (like images, files, or certificates) over text-based channels such as email, JSON APIs, and HTML data URIs.
How Base64 Decoding Works
- Each Base64 character represents 6 bits of data
- Four Base64 characters decode into three bytes of binary data
- Padding characters (
=) indicate the end of the encoded data when the input length wasn't a multiple of 3 - The decoder maps each character back to its 6-bit value and reassembles the original binary stream
Common Use Cases
- Data URIs: Decode images embedded in HTML or CSS
- JWT Tokens: Decode JSON Web Token payloads for debugging
- Email Attachments: Decode MIME-encoded email content
- API Responses: Decode binary payloads from REST APIs
- Certificates: Decode PEM-encoded SSL/TLS certificates