Base64 file converter
Convert files to Base64 and vice versa
TL;DR
What is Base64 file converter?
Base64 file conversion encodes any file (image, PDF, binary) into a Base64 ASCII string, or decodes a Base64 string back into its original file. This is the file-level counterpart to string encoding: the input is binary file data rather than text.
Common use cases
- ‣Email attachments: MIME encodes binary attachments as Base64 for transmission through text-only mail protocols
- ‣API payloads: send file contents as a Base64 string field in a JSON request body
- ‣Configuration embedding: bundle small binary assets (icons, certificates) directly into configuration files
- ‣Data URIs: produce a data: URI from any file for inline embedding in HTML or CSS
Frequently asked questions
What is the size overhead of Base64 encoding a file?
Base64 increases file size by approximately 33%. A 1 MB file becomes about 1.37 MB after encoding. This overhead is the trade-off for making binary data representable as plain text.
Is Base64 encoding the same as compression?
No. Base64 makes files larger, not smaller. For compression, use gzip, Brotli, or zstd before encoding. The two operations serve different purposes and are often combined: compress first, then encode for transport.