Image to Base64 (Data URI) Converter
Convert any image to a Base64 data URI - for inline CSS or HTML
Everything runs locally - the image never leaves your browser. Base64 encoding inflates size by ~33%; only inline small icons, not photos.
使い方
- 1Drop an image
Drag a file into the drop zone or click to pick - up to 10 MB.
- 2See the size impact
Base64 inflates size by ~33%. The tool shows original size, encoded size, and the overhead.
- 3Copy the format you need
Data URI on its own, CSS background-image, or a full <img> tag.
Image to Base64 (Data URI) Converter について
Free online image to Base64 converter. Drop or pick any image (PNG, JPG, SVG, GIF, WebP) to get a data URI ready to paste into CSS or HTML - with size analysis and one-click copy of the URI, a CSS declaration, or an <img> tag. Runs entirely in your browser. 712 Tools の Image to Base64 (Data URI) Converter はモダンな JavaScript API を使って完全にブラウザ内で動作します - サーバーがあなたのデータを見ることは一切ありません。つまり、即時の結果、完全なプライバシー、アップロード制限なしです。
デバッグ、簡単な確認、あるいは本番のインシデント対応まで - このツールは何度でも無料で使えます。ウォーターマークなし、サインアップなし、ツール内広告なし。
よくある質問
Is the image uploaded?
No. The file is read locally via FileReader - nothing leaves your browser.
When should I inline an image?
For tiny icons (under a few KB) where an extra HTTP request costs more than the size overhead. Never inline photos - the ~33% Base64 overhead kills page weight.
What about SVGs?
SVGs work fine as data URIs and are often small enough to inline. Consider URL-encoding rather than Base64 for SVG - it's actually smaller.
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