Reconstructing Binary Files from Base64
APIs and databases frequently serialize binary attachments into Base64 strings. This tool reconstructs the raw binary bytes into downloadable files with zero server roundtrips.
Frequently Asked Questions
How do I convert a Base64 string back into a downloadable file?
Paste your Base64 binary string into the input area, specify the desired file name and extension (e.g. archive.zip, document.docx, spreadsheet.xlsx), and click 'Reconstruct & Download File'.
Which file formats can be decoded from Base64?
Any binary file format! ZIP archives, Word documents (.docx), Excel sheets (.xlsx), PDF documents, executables (.exe), TAR files, fonts (.woff2), and images are 100% supported.
Is my file uploaded to any remote server?
No, the binary byte reconstruction and Blob creation happens entirely in your local browser sandbox.
Can I decode Base64 strings with 'data:...;base64,' headers?
Yes, our converter automatically strips Data URI prefixes and parses the clean Base64 payload.
What is the maximum file size supported?
You can decode binary files up to several tens of megabytes directly in modern web browsers.
How do I decode a Base64 file in Node.js?
In Node.js, use: 'const buffer = Buffer.from(base64String, "base64"); fs.writeFileSync("output.zip", buffer);'.