How to Convert Base64 to a File
Paste your Base64-encoded data into the input box above. If it's a complete data
URI (e.g. data:application/zip;base64,UEsDBBQA...), the MIME type is
extracted automatically. If it's a raw Base64 string, optionally enter a MIME
type - otherwise a generic binary type is used. Enter the filename you want for
the downloaded file, including its extension, then click
Decode & Prepare Download. A download button will appear,
ready to save the reconstructed file to your device.
Why Convert Base64 Back to a File?
Base64-encoded files commonly appear in API responses, database exports, email attachments, and configuration files - formats like ZIP archives, Word documents, PDFs, audio clips, fonts, certificates, and more are often transmitted as Base64 text. This tool reconstructs the original binary file from that text so you can inspect or use it directly, without writing a script.
Setting the Right Filename and MIME Type
| File type | Example filename | MIME type |
|---|---|---|
| ZIP archive | archive.zip | application/zip |
| Word document | document.docx | application/vnd.openxmlformats-officedocument.wordprocessingml.document |
| Excel spreadsheet | data.xlsx | application/vnd.openxmlformats-officedocument.spreadsheetml.sheet |
| MP3 audio | audio.mp3 | audio/mpeg |
| Font file | font.woff2 | font/woff2 |
The filename's extension determines how your operating system opens the file after download, so make sure it matches the actual file type. If you're working with images or PDFs specifically, our dedicated Base64 to Image and Base64 to PDF tools provide inline previews as well.
Frequently Asked Questions
Any file type. Base64 simply represents raw binary data as text, so this tool can reconstruct ZIP archives, Office documents, audio files, fonts, executables, or anything else - as long as you set the correct filename and extension.
Enter a filename with its extension (e.g. "report.pdf" or "music.mp3"). If your Base64 string is a full data URI, the MIME type is detected automatically; otherwise you can specify one manually in the MIME type field.
This usually happens when the Base64 string is incomplete or contains extra characters like line breaks that changed the data. Verify the full, unmodified string was pasted.
No. Decoding happens entirely in your browser, producing a local file object that's offered as a direct download. Nothing is sent to or stored on any server.