Base64 Encoder and Decoder
Encode Unicode text to Base64 or decode Base64 back to UTF-8.
Your input stays on this device and is processed in your browser.How to use Base64 Encoder and Decoder
- Choose the standard or URL-safe Base64 alphabet.
- Enter Unicode text to encode or a Base64 value to decode as UTF-8.
- Copy the result or use it as the next input to verify a round trip.
Text representation, not encryption
Base64 exists so binary data can travel through channels that only accept text, such as an email body or a JSON string. It represents three bytes with four printable characters, which is why an encoded value is always about a third larger than what went in.
Anyone can decode it, instantly, without a key. That is not a weakness in the encoding — it is the whole design. A token, a password or a connection string that is only Base64 is stored in plain sight, and encoding is a transport step, never a protection step.
This tool treats decoded bytes as strict UTF-8 text and says so when they are not, rather than showing replacement characters. That means an encoded image or archive will be reported as invalid: those are bytes with no text reading, and there would be nothing useful to display.
Frequently asked questions about Base64 Encoder and Decoder
Does the tool support emoji and Polish characters?
Yes. Text is converted through UTF-8, so Unicode characters such as emoji and Polish letters round-trip correctly.
What does URL-safe Base64 change?
It replaces plus and slash with hyphen and underscore and omits trailing padding so the value is easier to place in URLs.
Is Base64 a form of encryption?
No. Base64 only represents bytes as text and offers no confidentiality. Anyone can decode a Base64 value.