What is Base64?
Base64 is a way to write any data — text, an image, a file — using only Latin letters, digits and +, /, =. It’s used wherever only text is allowed: email, JSON, data URLs and HTTP headers such as Authorization: Basic.
Base64 is encoding, not encryption: anyone can decode it, no password needed.
How to use
Choose “Encode” or “Decode” and paste your text — the result appears instantly. Text is encoded as UTF-8, so accented letters and emoji work correctly. When decoding, the URL-safe variant (- and _ instead of + and /) and strings without trailing = are accepted too. For URLs, JWTs and file names there’s “Encode (URL-safe)”: - and _ instead of + and /, with no trailing =.
Examples
Hello, world!→SGVsbG8sIHdvcmxkIQ==aGVsbG8=→hello
FAQ
Why is the encoded string longer? Every 3 bytes become 4 characters, so the size grows by about a third.
What do the = signs at the end mean? They’re padding: with padding, the length is a multiple of 4. Unpadded Base64 is also accepted here.
Why do I get an error when decoding? The string contains invalid characters, or the decoded data isn’t text (an image, for example).
For links, use the URL encoder.