Base64 Decoder

Decoding reverses Base64 encoding. It turns the text string made of letters, digits, plus and slash back into the original bytes, which can be readable text or a binary file such as an image or PDF.

Paste the Base64 string into the input box and click Decode. If the bytes are valid UTF-8 text, the readable result appears in the output box and you can copy or download it.

Paste the Base64 string, or the whole data URI starting with data:image/png;base64, and click Decode. When the data is not text, a Download file button appears and saves it with the right extension, such as .png, .jpg, .pdf or .mp3.

Yes. If your input starts with data: followed by a type, the tool reads the file type, removes the prefix and decodes the rest. You do not need to cut the string by hand.

Yes. Hyphens and underscores are converted back to plus and slash automatically, and missing equals padding is added, so URL-safe strings and token parts decode without extra steps.

Valid Base64 only contains A to Z, a to z, 0 to 9, plus, slash and up to two equals signs at the end. Common causes of errors are extra characters, a copied quotation mark or comma, text that was cut off, or a string that is not Base64 at all. Spaces and line breaks are ignored.

That means the data is not UTF-8 text. It is probably binary, such as an image, a compressed file or encrypted data. The tool detects this and offers a file download instead of showing garbled text.

Base64 is only an encoding, so anyone can decode it, which is why it is not a way to protect secrets. If decoding shows a hash or random bytes, it is a different format and cannot be reversed here.

No. Decoding is done in your browser. Your strings and files are never sent, stored or logged.

Yes. Decoded bytes are read as UTF-8, so accented letters, Arabic, Chinese and emoji are shown correctly.

Use the Base64 encoder. It converts text or files to Base64, with URL-safe and line wrap options.

Yes. It is free with no sign-up and works on phones, tablets and computers.