Programming tool
Base64 Encoder / Decoder
Convert text to Base64 or turn Base64 back into readable Unicode text, entirely in your browser.
Unicode text is supported.
Base64 result
What is Base64?
Base64 is a text representation for binary data. It uses 64 characters to make bytes easier to store or send through systems designed for text, such as email, JSON, and URLs.
How Base64 encoding works
Encoding converts your text to UTF-8 bytes, groups those bytes into six-bit values, and maps each value to a Base64 character. Padding with equals signs may be added so the result fits complete groups.
Encoding is not encryption
Base64 does not protect secrets or require a key. Anyone can decode it, so use encryption for passwords, tokens, personal data, and anything confidential.
Common Base64 uses
Base64 is commonly used for email attachments, data URLs, API payloads, configuration values, and embedding small binary files in text formats. It usually increases data size by about one third.
Unicode and Base64
This tool encodes Unicode as UTF-8 before converting it to Base64, so characters such as こんにちは, مرحبا, emoji, and ✓ round-trip correctly. Decoding expects UTF-8 text.
Frequently asked questions
Does this tool send my text anywhere?
No. Encoding and decoding happen in your browser. No API request is needed, and decoded content is treated only as text.
Why does Base64 make data larger?
Base64 represents every 6 bits with one character. Because text characters carry fewer useful bits than the original bytes, the encoded form is typically around 33% larger.
Why was my Base64 rejected?
The value may contain unsupported characters, incorrect padding, or bytes that are not valid UTF-8 text. Whitespace is allowed and removed before validation.