File ↔ Base64

Encode a file as Base64 (optionally a data URL) or paste Base64 to reconstruct the file.

Converter Media & Files Updated Apr 19, 2026
How to Use
  1. Drop a file to get Base64 / data URL.
  2. Paste Base64 to reconstruct a file for download.
Encode
Drop file to encode
Any file, any size (memory-permitting)
Decode
Output

Notes

Alphabet
A-Z a-z 0-9 + / =
URL variant
- and _ no padding
Overhead
~33%
Data URL
data:mime;base64,…
Wrap 76
RFC 2045
MIME default.
Privacy
Local

Frequently Asked Questions

Data URL?

data:mime;base64,<payload> — embeddable directly in HTML/CSS.

Size overhead?

~33% bigger than source.

Common Use Cases

Email inline

Embed images in email HTML.

Test fixtures

Inline binary blobs in tests.

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