Is my image uploaded anywhere?

No. The image is read locally with your browser's FileReader and encoded in memory — it is never uploaded, stored or seen by anyone.

Is the data URI an exact copy of my image?

Yes. FileReader encodes the original file bytes as base64 without re-compressing, so the embedded image is byte-for-byte identical to the file you selected.

Why is the data URI bigger than my file?

Base64 encoding adds roughly 33% to the size, so data URIs suit small icons and inline assets rather than large photos, where a normal file link is more efficient.

What output formats can I copy?

You can copy the raw data URI, a ready-made HTML img tag with the URI as its src, or a CSS background-image rule, so it drops straight into whatever file you are editing.

Do data URIs work in email?

They work in most web pages and many email clients, but some email clients (notably parts of Outlook) block or strip inline base64 images, so test before relying on them for newsletters.

What image formats are supported?

Any format your browser can read as a file — JPEG, PNG, WebP, GIF, SVG and more. The MIME type in the data URI is taken from the file you select, so the encoding matches the original format.

Image to Base64 Data URI

Turn an image into a base64 data URI without uploading it

A data URI lets you embed an image directly inside your HTML, CSS or Markdown instead of linking to a separate file — handy for tiny icons, email templates, self-contained pages and offline demos. This tool reads your image and produces a data:image/...;base64,... string, with optional ready-to-paste HTML <img> or CSS background-image wrappers.

How it works

The browser’s FileReader.readAsDataURL reads the original file bytes and encodes them as base64 without re-compressing, prefixing the MIME type detected from the file. The result is a single string of the form:

data:image/png;base64,iVBORw0KGgoAAAANS...

You can then copy it raw, or wrapped as <img src="..."> or background-image: url(...). Because base64 uses 4 characters for every 3 bytes, the encoded string is about 33% larger than the source file.

Example

Source	Output
`icon.png` (1.2 KB)	`data:image/png;base64,...` (~1.6 KB string)
HTML wrapper	`<img src="data:image/png;base64,...">`
CSS wrapper	`background-image: url("data:image/png;base64,...")`

The image is read locally with your browser’s FileReader, so it is never uploaded, stored, or seen by anyone. Data URIs are best for small assets rather than large photos.