Base64 Converter
Paste some text to encode it, or paste Base64 to decode it. Special characters, accents and emoji are handled correctly.
Be the first to rate this tool
The formula
Every 3 bytes of input become 4 characters from the set A-Z, a-z, 0-9, + and /. Padding with = fills the last group.
What Base64 is for
Base64 turns binary data into plain text characters so it can travel through systems that only handle text, such as emails, JSON, URLs and HTML. It is encoding, not encryption: anyone can decode it, so never use it to hide a password.
An example
The word "hello" becomes aGVsbG8=. Decoding aGVsbG8= gives "hello" back. Base64 makes data about 33 percent bigger, because 3 bytes become 4 characters.
URL-safe Base64
The standard alphabet contains + and /, which have special meanings in web addresses. The URL-safe variant swaps them for - and _ and drops the = padding. Tick the box when you encode something that will live in a link, such as a token.
UTF-8 and emoji
Plain Base64 functions in browsers break on characters outside basic Latin. This tool first turns your text into UTF-8 bytes, so accents, other alphabets and emoji round-trip correctly.
Examples to check
Type these into the calculator above to see how it behaves. Every result below was produced by the same calculator code that runs on this page.
| What you enter | What you get |
|---|---|
| Encode text to Base64; Input: hello | Base64: aGVsbG8= |
| Encode text to Base64; Input: CalculatorStop | Base64: Q2FsY3VsYXRvclN0b3A= |
| Decode Base64 to text; Input: aGVsbG8gd29ybGQ= | Decoded text: hello world |
Base64 Converter: frequently asked questions
Is Base64 secure?
No. It is a reversible format, not encryption. Treat anything encoded this way as readable by anyone.
Why does decoding fail?
The input probably has characters outside the Base64 alphabet, or the wrong length. Remove spaces or line breaks that were added by mistake, and check for missing characters.
Is my text sent anywhere?
No. Encoding and decoding happen in your browser.
Does the conversion happen on my device?
Yes. Your text, colours and files are processed in your browser and never uploaded.
Is what I enter in this converter saved or sent anywhere?
No. The calculation runs in your browser, so what you enter is not sent to our servers. We only count, anonymously, whether a tool ran successfully.
Is this converter free to use?
Yes. It is free, needs no sign-up and has no usage limit.
Last reviewed: October 3, 2026