Data encoding

Base64 Encoder Decoder

Encode Unicode text and local files to Base64, decode Base64 to UTF-8 or binary data, validate standard and URL-safe alphabets, and inspect byte counts in your browser.

Base64 input

Encode or decode

UTF-8 + binary

Output

Validation

Base64 result details

Input characters
Payload bytes
Output characters
Padding characters
Selected alphabet
Validation

Base64 notes

Text encodingUnicode text is converted to UTF-8 bytes before Base64 encoding.
PaddingStandard Base64 may end with = or == so its length is a multiple of four.
URL-safe Base64URL-safe mode replaces + and / with - and _ and commonly omits padding.
Not encryptionBase64 is reversible encoding and must not be used to protect secrets.

Base64 character reference

VariantCharactersNotes
StandardA-Z a-z 0-9 + /MIME and general Base64 alphabet
URL-safeA-Z a-z 0-9 - _Suitable for URLs, filenames and tokens
Padding=Fills encoded length to a multiple of four
Line wrap76Common MIME line length

Popular Base64 examples

Base64 FAQ

Is Base64 encryption?

No. Base64 is reversible encoding and does not protect secrets.

Why does Base64 end with equals signs?

Equals signs are padding that makes the encoded length a multiple of four.

What is URL-safe Base64?

It replaces + with - and / with _, and often omits padding.

Can this tool encode files?

Yes. Files up to 10 MB are encoded locally in your browser and are not uploaded.