Decode Base64 to Text or a File
Paste Base64, Base64URL or a data: URL to get the original content back. Readable text is shown immediately; binary data such as images, PDFs or ZIP archives is identified by its signature and can be saved as a file.
How to decode Base64
- Paste the Base64 string; line breaks, spaces and missing = padding are tolerated.
- If the bytes are UTF-8 text, the decoded text appears on the right and can be copied.
- If the data is binary, check the detected type and click Download file to save it with a matching extension.
Supported formats
- Input
- Base64, Base64URL, data: URL
- Output
- Text, Binary file
Benefits
- Accepts both the standard and URL-safe alphabets and strips data: URL prefixes.
- Detects common file types (PNG, JPEG, PDF, ZIP, MP3 and more) from the decoded bytes.
- Points to the exact position of the first invalid character.
Limitations
- Type detection reads file signatures, so formats without a known signature are saved as .bin.
- Text in legacy encodings (for example Windows-1252 or Shift-JIS) is treated as binary because only UTF-8 is decoded as text.
Privacy and security
Decoding runs in this tab. Downloads are created from memory with a temporary object URL; nothing is uploaded.
Read our privacy policy for details about the site as a whole.
Frequently asked questions
Why do I get "not a valid Base64 character"?
The input contains a character outside the Base64 alphabets, such as a quote, a % sign from URL encoding, or a stray symbol from copying. Remove it or decode the URL encoding first.
Can I decode an image back to a picture?
Yes — the decoder recognises the image signature and the download is saved as .png, .jpg and so on. For a visual preview, the Base64 to Image tool shows the picture directly.
Does missing padding matter?
Not here. Base64URL normally omits the trailing = characters, and the decoder reconstructs the bytes without them.