What is Base64 image encoding?

Base64 converts binary image data into a text string of letters, digits, + and /. The encoded image can be embedded directly in HTML, CSS, or JSON as a data URI (data:image/png;base64,...) instead of being loaded from a separate file.

When should I embed images as Base64?

For small images (under ~5–10 KB) like icons and logos where eliminating an HTTP request outweighs the size increase — especially in emails, single-file HTML documents, and CSS sprites replacements.

Does Base64 make images larger?

Yes — encoding adds roughly 33% to the file size because every 3 bytes of binary become 4 text characters. Gzip compression on the server recovers some of this, but large photos should stay as normal files.

How do I use the Base64 output in HTML and CSS?

HTML: . CSS: background-image: url(data:image/png;base64,iVBOR...). The tool generates both snippets ready to copy.

Is my image uploaded to a server?

No — encoding happens in your browser using the FileReader API. The image never leaves your device.

Image to Base64 Converter — Free Data URI Encoder

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Image to Base64 Converter — Embed Images as Code

Sometimes an image needs to live inside the code itself: an icon in a single-file HTML report, a logo in an email template, a texture in a JSON payload. This free converter encodes any image to Base64 in your browser and hands you the raw string, the data URI, and ready-to-paste HTML and CSS snippets. The file never uploads anywhere — the FileReader API does everything locally.

Output Formats Provided

Raw Base64:   iVBORw0KGgoAAAANSUhEUg...
Data URI:     data:image/png;base64,iVBORw0KGgo...
HTML:         <img src="data:image/png;base64,iVBORw..." alt="">
CSS:          background-image: url(data:image/png;base64,iVBORw...);

When Base64 Embedding Wins

Email templates — some clients block external images by default; embedded images always render (though watch total email size).
Single-file deliverables — HTML reports, offline docs, and widgets that must work with zero external requests.
Tiny UI assets — icons and 1px patterns where an HTTP request costs more than the bytes saved.
APIs and JSON — transmitting small images inside JSON payloads where multipart uploads aren't available.

When to Avoid It

Base64 inflates size ~33% and embedded images can't be cached independently — every page load re-downloads them inside the HTML/CSS. Photos, hero images, and anything over ~10 KB should remain normal files served with proper caching headers (or better, modern formats like WebP/AVIF via an img tag). The rule of thumb: embed icons, link photos.

How Base64 Actually Works

Binary data is grouped into 24-bit chunks, each split into four 6-bit values, and each value mapped to one of 64 safe ASCII characters (A–Z, a–z, 0–9, +, /) with = padding the final block. The result survives any text-only channel — email bodies, JSON strings, CSS files — that would corrupt raw binary.

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No upload, no signup, no size tracking. Encode as many images as you need directly on your device.

Image To Base64

Result