What Is Base64 Encoding?

Base64 is a binary-to-text encoding scheme that converts binary data into an ASCII string format. It is widely used to embed data in text-based formats like HTML, CSS, JSON, and email.

Common Use Cases

Data URIs: Embedding images directly in HTML or CSS.
API payloads: Encoding binary data for JSON APIs.
Email attachments: MIME encoding for email content.
Authentication: HTTP Basic Authentication headers.

How It Works

Base64 takes every 3 bytes of input and converts them into 4 ASCII characters, using a set of 64 characters (A-Z, a-z, 0-9, +, /). This means Base64-encoded data is about 33% larger than the original.

Frequently Asked Questions

Does this tool support Unicode?

Yes. This tool properly handles Unicode text including Japanese, emoji, and other multi-byte characters by using UTF-8 encoding.

Is Base64 encryption?

No. Base64 is an encoding, not encryption. It does not provide any security — anyone can decode a Base64 string. Never use Base64 to protect sensitive data.