Can it generate a data URI?

Yes. Choose the data URI input profile and set a MIME type; the output is a ready-to-embed data: string for CSS backgrounds or HTML.

Does it handle Unicode text and emoji?

Yes. Text is UTF-8 encoded before the Base64 step, so non-ASCII characters survive an encode and decode round trip.

Is Base64 encryption?

No. Base64 is an encoding, not encryption: anyone can decode it without a key. Never use it to hide passwords or secrets.

Why does Base64 output end with = or ==?

Base64 works in groups of 3 bytes. When the input length is not a multiple of 3, the output is padded with one or two = characters so its length is a multiple of 4.

What is the difference between Base64 and Base64url?

Base64url replaces + with - and / with _ so the result is safe in URLs and file names, and it usually omits the = padding. To decode Base64url with a standard decoder, swap those characters back and add padding to a multiple of 4.

Why is the encoded text bigger than the original?

Each 3 input bytes become 4 output characters, so Base64 is about 33% larger than the input, plus any padding.

Is my payload uploaded when I encode it?

No. Encoding and decoding run entirely in your browser and nothing is uploaded.

Base64 encoder and decoder

Base64 is an encoding that represents binary data using 64 printable characters (A-Z, a-z, 0-9, + and /), so it can travel safely through text-only channels.

Encode text to Base64 or decode it back, with UTF-8 support and ready-to-paste data URIs for CSS and HTML. Free, and nothing leaves your browser.

Browser-sideNo accountCopy, download, or print

Last reviewed 30 Oct 2026

Your inputs are saved as a draft in this browser only. Nothing is uploaded.

Jump to result

Result

Input characters13

Output characters20

SGVsbG8sIHdvcmxkIQ==

SGVsbG8sIHdvcmxkIQ==

Examples

Encode a word

"Hello" encodes to SGVsbG8=. The = is padding, because 5 bytes do not divide evenly into 3-byte groups.

Encode a sentence

"Hello, world!" encodes to SGVsbG8sIHdvcmxkIQ==.

Unicode text

"₹100" encodes to 4oK5MTAw. The rupee sign is 3 bytes in UTF-8, so it takes 4 Base64 characters on its own.

Decode

U2FtcGxlIHRleHQ= decodes to "Sample text".

Data URI

Encoding "Hello" with the data URI profile and MIME type text/plain gives data:text/plain;base64,SGVsbG8=, which you can use in an href or a CSS url().

Base64url

"??>" encodes to Pz8+ in standard Base64 and Pz8- in Base64url, which replaces + with - and / with _ and usually drops the = padding. JWTs use Base64url.

Size overhead

Every 3 bytes become 4 characters, so a 1,024-byte file becomes 1,368 Base64 characters, about a third larger.

How to use it

Choose the operation: encode text or decode Base64.
Pick an input profile: plain text, data URI, or file payload metadata.
For data URIs, set the MIME type and file name.
Paste your text or Base64 payload and copy the result.

Questions

Can it generate a data URI?: Yes. Choose the data URI input profile and set a MIME type; the output is a ready-to-embed data: string for CSS backgrounds or HTML.
Does it handle Unicode text and emoji?: Yes. Text is UTF-8 encoded before the Base64 step, so non-ASCII characters survive an encode and decode round trip.
Is Base64 encryption?: No. Base64 is an encoding, not encryption: anyone can decode it without a key. Never use it to hide passwords or secrets.
Why does Base64 output end with = or ==?: Base64 works in groups of 3 bytes. When the input length is not a multiple of 3, the output is padded with one or two = characters so its length is a multiple of 4.
What is the difference between Base64 and Base64url?: Base64url replaces + with - and / with _ so the result is safe in URLs and file names, and it usually omits the = padding. To decode Base64url with a standard decoder, swap those characters back and add padding to a multiple of 4.
Why is the encoded text bigger than the original?: Each 3 input bytes become 4 output characters, so Base64 is about 33% larger than the input, plus any padding.
Is my payload uploaded when I encode it?: No. Encoding and decoding run entirely in your browser and nothing is uploaded.