Base64 Encoder & Decoder

Base64 is a way of writing any file — a picture, a PDF, a sound clip — using only a small set of plain text characters: the letters A to Z in both cases, the digits 0 to 9, and a couple of symbols. Computers store files as raw bytes, but a lot of systems can only carry text safely. Base64 bridges that gap by turning those bytes into a long, harmless-looking string of letters and numbers that can travel anywhere text can go, then be rebuilt into the exact original file at the other end. It is worth being clear that it is neither encryption nor compression — it is best thought of as a universal text envelope for binary data.

The usual reason is to place a file directly inside something that only understands text. Developers embed small images straight into HTML, CSS or JSON as Base64 so the browser does not have to fetch them separately, which can speed up a page. It is also handy for pasting a file into a system that strips attachments, tucking a logo into a configuration file, or pushing binary data through an API or email body that expects plain text. In short, whenever you need to “inline” a file rather than link to it, Base64 is normally the tool people reach for.

It is important to be honest about this: Base64 is not a security measure. It rewrites a file as letters and numbers, but anyone can decode it straight back with no password or key — including this very page. So although a Base64 string looks unreadable at a glance, it gives no real protection and should never be mistaken for encryption. If you genuinely need to keep something private, encrypt it first with a proper tool and then Base64-encode the encrypted result if a text format is required. The one privacy benefit here is practical rather than cryptographic: because the conversion runs entirely in your browser, the encoding step never hands your file to anyone else.

Yes, and it catches people off guard. Base64 represents every three bytes of the original using four text characters, so the encoded version is always larger — roughly a third bigger, plus a little overhead. That growth is simply the price of making binary data safe to move around as text. It is also why Base64 suits small things like icons and short snippets far better than large videos or archives. If your real goal is a smaller file rather than a text-safe one, you want the compression tools on this site instead, not Base64.

Absolutely — that is exactly what Decode mode does. Paste or drop in a Base64 string and the tool reverses the process, rebuilding the file byte for byte so it is identical to what you started with. Our encoder even stores the original filename and file type inside the encoded text, which means that when you decode it the file returns with the right name and opens in the right program. Encoding and decoding are simply the two halves of one round trip, with nothing lost in between.

No. Every conversion happens locally, right inside your web browser, using code that runs on your own device. Your files are never sent to our servers, never stored, and never seen by us — there is simply nowhere for them to go. A nice side effect is that the tool keeps working even if your connection drops, and sensitive documents stay entirely on your machine. When you close the tab the data clears from memory and nothing is left behind.