Base64 Encode and Decode

Convert text or files to Base64 and back. Pick the character set, wrap lines for email, or make the output URL-safe.

Text to encode

46 characters · 54 bytes in UTF-8

Base64 result

SGVsbG8sIHdvcmxkIQpHcsO8w59lIGF1cyBNw7xuY2hlbiDigJQgMyDDlyA0ID0gMTIg4pyT

72 Base64 characters · 133% of input size

CharsetNewline Each line separately Wrap at 76 chars (MIME) URL-safe (-_ , no padding) Live

How the first 3 bytes become 4 characters

Base64 reads the bytes as one stream of bits and cuts it into 6-bit groups. Each group is a number from 0 to 63, which picks a character from the alphabet. Colors show which byte each bit came from.

H0x48 · 72

e0x65 · 101

l0x6C · 108

S18

V21

s44

Alphabet A–Z a–z 0–9 + /Size 4 chars per 3 bytes (+33%)Padding = fills the last groupSpec RFC 4648, MIME line wrap RFC 2045

Encode a file

Turn an image, PDF or any other file into Base64, for example to embed it in CSS, HTML or a JSON payload. Files up to 50 MB. Nothing leaves your browser.

Drop a file hereor click to choose one

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Data URI prefix Wrap at 76

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