Base64 File Decoder
Decode Base64 encoded strings back to downloadable files instantly. Extract files from Base64 data, API responses, or data URIs. Supports all file types.
Specify the filename with extension (e.g., document.pdf, archive.zip, data.json)
Decoded File Information
Filename:
File Size:
Base64 Length: characters
Status: ✓ Ready to download
Click the "Decode & Download" button above to download your file.
What is Base64 File Decoding?
Base64 file decoding converts Base64 encoded strings back into their original binary file format. This is essential when receiving files through APIs, extracting attachments from JSON, or converting data URIs back to downloadable files.
Common Use Cases
API Responses: Many APIs return file data as Base64 strings. Decode them to save the actual files to your device.
Email Attachments: Extract file attachments that were Base64 encoded in email MIME data.
Data URIs: Convert data URIs (data:application/pdf;base64,...) back to downloadable files.
Database Exports: Retrieve files that were stored as Base64 strings in database text fields.
How to Use This Tool
Step 1: Paste your Base64 encoded string into the text area. You can paste the pure Base64 string or include the data URI prefix (data:application/pdf;base64,...)—the tool will handle both.
Step 2: Optionally specify an output filename with the correct file extension (e.g., report.pdf, data.json, archive.zip).
Step 3: Click "Decode & Download" to decode the Base64 and automatically download the file to your device.
Troubleshooting
Invalid Base64 Error: Make sure you copied the complete Base64 string. Remove any extra spaces, line breaks, or invalid characters.
File Won't Open: Ensure you specified the correct file extension. The decoded binary data needs the right extension to be recognized by your operating system.
Browser Hangs: Very large Base64 strings (over 50MB) may cause browser performance issues. Try using a smaller file or a desktop application for large files.
Privacy and Security
All decoding happens locally in your browser. Your Base64 data is never sent to any server. Files are generated and downloaded directly from your browser's memory, ensuring complete privacy for sensitive or confidential files.