Base64 Encoder & Decoder
Encode UTF-8 text as Base64 or decode Base64 back to text.
Result
What is Base64?
Base64 is an encoding method that represents binary data with ASCII characters. It is not encryption and should not be used to protect secrets.
When to encode text
This tool converts entered text to UTF-8 bytes before Base64 encoding. For example, Hi becomes SGk=. This can represent bytes in a text-only field such as JSON, but the tool does not read files or build a complete data URL. Input is limited to 1,000,000 characters.
Why the output grows and may end with =
Base64 represents three input bytes with four characters, so longer inputs generally grow by about 33%. An equals sign pads an incomplete final group. Korean text and emoji are converted to UTF-8 first, so the size depends on bytes rather than visible characters.
Decode errors and security limits
Malformed Base64 produces a format error. Well-formed Base64 whose decoded bytes are not valid UTF-8 produces a different error. Whitespace is removed before decoding. Base64 is not encryption: anyone can recover the text, so do not use it to protect passwords or tokens.
Standard reference
Frequently Asked Questions
Can I convert images or files?
No. This tool converts entered UTF-8 text only; it does not accept binary files or file uploads.
Is Base64 encryption?
No. Anyone can decode it, so do not use Base64 to protect passwords or confidential information.
Is my input sent to a server?
No. Your text and result stay in the browser and are not stored on the server. After a successful conversion, only a Tool-run statistics request is sent, without your input.