What is Base64?
Base64 is a way to represent any data using only 64 safe characters: letters, numbers, + and /. It is used to send data through systems that only handle plain text, like email, URLs, JSON or HTML. For example, "Hello" becomes "SGVsbG8=".
How to encode or decode Base64
- Choose Encode to convert text to Base64, or Decode to convert Base64 back to text.
- Type or paste your content in the input box.
- The result appears instantly. Click the copy button to copy it.
Common uses of Base64
- JWT tokens: decode the header and payload of a JSON Web Token to read its content.
- APIs: send credentials in HTTP Basic authentication headers, or binary data inside JSON.
- Emails: attachments are encoded in Base64 inside the email source.
- Data URLs: embed small images or fonts directly in HTML and CSS.
- Debugging: read Base64 values found in logs, cookies or configuration files.
Frequently asked questions
How do I decode a Base64 string?
Select Decode, then paste your Base64 string in the input box. The decoded text appears instantly. If the string is not valid Base64, an error message is shown instead.
Is Base64 a form of encryption?
No. Base64 is an encoding, not encryption. Anyone can decode it without a key, so never use it to protect passwords or sensitive data.
Does it support accents, emojis and other special characters?
Yes. Text is converted to UTF-8 before being encoded, so accented letters, emojis and non Latin alphabets are encoded and decoded correctly.
Does it work with URL safe Base64?
Yes. When decoding, URL safe characters (- and _) and missing = padding are handled automatically, which is useful for JWT tokens.
Why is the Base64 result longer than my text?
Base64 uses 4 characters to represent every 3 bytes of data, so the encoded result is always about 33% larger than the original.
Is my data sent to a server?
No. Encoding and decoding happen directly in your browser. Nothing is saved or sent anywhere.
Related tools
- Case converter: switch text between uppercase, lowercase, camelCase and more.
- Reverse string: write any text backwards in one click.