Base64 Decoder
Decode Base64 strings and files back to original text and files with file upload support.
Base64 decoding is the reverse process of Base64 encoding. It converts Base64-encoded strings back to their original binary or text format. This is essential when you receive Base64-encoded data and need to restore it to its original form.
Our Base64 decoder supports decoding both text strings and files. You can paste a Base64 string or upload a Base64-encoded file, and our tool will decode it back to the original content.
All decoding happens in your browser - your data never leaves your device, ensuring complete privacy and security.
Base64 decoding reverses the encoding process:
- Character Mapping: Converts each Base64 character back to its 6-bit binary value
- Grouping: Groups 4 Base64 characters (24 bits) back into 3 bytes of binary data
- Padding Removal: Removes padding characters (=) and adjusts the output accordingly
- Binary Conversion: Converts the binary data back to the original text or binary format
- Output: Produces the original data that was encoded
Our decoder automatically detects the original file type and restores the correct filename and extension when decoding files.
API Responses
Decode Base64-encoded data received from APIs. Many APIs return binary data (like images) as Base64 strings that need to be decoded.
Email Attachments
Decode Base64-encoded email attachments to restore the original files. Email clients handle this automatically, but you may need to decode manually in some cases.
Data URLs
Extract files from data URLs. Decode the Base64 portion of data URLs to get the original file content.
Database Content
Decode Base64-encoded content stored in databases. Some systems store binary data as Base64 strings that need to be decoded for use.