Free Base64 Encoder & Decoder Online
Convert text to Base64 or decode Base64 back to text. Supports file-to-Base64 conversion. Everything runs in your browser.
What Is Base64?
Base64 is a binary-to-text encoding scheme that represents binary data as an ASCII string. It uses 64 characters (A-Z, a-z, 0-9, +, /) to encode data, making it safe to transmit through text-based protocols. Note that Base64 is encoding, not encryption · it does not provide security.
Common Uses for Base64
- Data URIs · Embed small images directly in HTML or CSS without extra HTTP requests.
- REST APIs · Transmit binary data (files, images) in JSON payloads.
- Email (MIME) · Encode attachments for email protocols that only support text.
- Authentication · HTTP Basic Auth encodes credentials as Base64 (though this is not encryption).
- Storing binary in text formats · Safely embed binary data in JSON, XML, or CSV files.
Frequently Asked Questions
Is Base64 secure?
No. Base64 is encoding, not encryption. Anyone can decode a Base64 string. Never use Base64 to protect sensitive data · use proper encryption (AES, RSA) for security.
Why does Base64 make files larger?
Base64 encoding increases data size by approximately 33%. Three bytes of binary data become four Base64 characters. This overhead is the trade-off for being able to transmit binary data as text.
Can I encode files?
Yes! Drag and drop any file onto the encoder, or click to browse. The file will be converted to a Base64 data URI that you can paste directly into HTML, CSS, or JavaScript.