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Image to Base64 Converter — Encode for CSS or HTML Inline Use

Upload an image to convert it to a Base64 data URI, ready to paste directly into a CSS background-image: url(...) declaration or an HTML <img src="data:...">, eliminating a separate file request for small icons and inline assets. Conversion happens entirely in your browser.

How to use Image to Base64

1. Upload your image.
2. Copy the generated data: URI.
3. Paste it into your CSS or HTML.

Frequently asked questions

When should I inline an image as Base64 instead of linking it?

For small icons and assets where saving an extra HTTP request outweighs the roughly 33% size increase Base64 encoding adds — not a good fit for large photos.

Why is the encoded string about a third larger than the original file?

Base64 encodes every 3 bytes of binary data as 4 ASCII characters, which is an inherent property of the encoding, not a flaw in the conversion.

Is my image uploaded to a server?

No. The conversion runs entirely in your browser using the File API.

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Also searched for: image to base64 converter online · convert image to data uri · base64 encode image for css

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