HTML crossorigin Attribute: Reference and Examples

The crossorigin attribute is a small instruction attached to an HTML element. Its job is to control CORS requests for embedded resources. It is easier to remember when you can see it in a real piece of markup.

What crossorigin is used for

Control CORS requests for embedded resources. The attribute appears inside an element’s opening tag. Depending on its definition, it may take a specific string, a number, an enumerated keyword, or be a boolean attribute.

The example below uses it in a img context. Other elements may support it too, or may give the same attribute a different meaning.

Example you can try

<figure>
    <img src="photo.jpg" alt="A sunny mountain trail" width="600" height="400" crossorigin="anonymous">
    <figcaption>Mountain trail</figcaption>
</figure>

How the example works

Look for crossorigin in the snippet. Here the example shows the value anonymous. This is a concrete input the browser can interpret; it is not just text shown to the reader.

A cross-origin request may fail without matching response headers from the resource server.

Values and important behavior

anonymous requests without cross-origin credentials; use-credentials includes credentials when allowed by CORS policy.

This detail matters most when the page receives user input, navigates to another document, or loads an external resource. In those cases, check the browser behavior and any server-side requirements separately.

Small practice task

Copy the code and change crossorigin to another sensible value, or remove it entirely if it is optional. Test the difference in the browser and inspect any submitted value or network request.

Common Beginner Mistakes

• A cross-origin request may fail without matching response headers from the resource server.
• Using crossorigin on an element that does not support it.
• Believing that an HTML hint or client-side check replaces real server validation or a security policy.

Key Takeaways

• crossorigin is used to control CORS requests for embedded resources.
• A cross-origin request may fail without matching response headers from the resource server.
• Choose valid values and test the result instead of guessing what the browser will do.