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Base64 Encoder

Encode text or data to Base64 format instantly.

What Is Base64 Encoding?

Base64 is a binary-to-text encoding scheme that represents binary data using only 64 printable ASCII characters: A–Z, a–z, 0–9, +, and /. Padding characters (=) are appended to make the output length a multiple of 4.

When to Use Base64

Data URLs: Embed images, fonts, or other binary files directly in HTML/CSS without a separate HTTP request. A Base64-encoded PNG looks like data:image/png;base64,iVBOR....

API payloads: When sending binary data through a JSON or XML API that only handles text, Base64 is the standard way to safely transport the bytes.

Email attachments: The MIME standard uses Base64 to encode file attachments so they can travel safely over email protocols designed for plain text.

Quick Example

The text Hello encodes to SGVsbG8=. Every 3 bytes of input become 4 Base64 characters, so the output is roughly 33% larger than the input.

Base64 vs Base64URL

Standard Base64 uses + and /, which have special meaning in URLs. If you need to include the result in a URL or JWT token, use the Base64URL Encoder instead.

Need more encoding tools? Try the full Encode & Decode suite.