HTML loadeddata DOM Event: Reference and Examples

When someone interacts with a webpage, the browser sends events to the relevant JavaScript code. The loadeddata event happens when the browser loads the first media frame.

When loadeddata happens

The browser loads the first media frame.

You can listen for it using addEventListener(). That keeps event handling separate from HTML attributes such as onclick and works well with modern code organization.

A small working example

<video id="demo-target" controls preload="metadata" width="320">
    <source src="sample-video.mp4" type="video/mp4">
</video>
<p id="event-status" role="status">Waiting for loadeddata...</p>
<script>
    const eventTarget = document.getElementById("demo-target");
    const eventStatus = document.getElementById("event-status");

    if (eventTarget) {
        eventTarget.addEventListener("loadeddata", (eventDetails) => {
            eventStatus.textContent = "loadeddata event received";
            console.log(eventDetails.type, eventDetails.target);
        });
    }
</script>

Reading the code

The browser listens for loadeddata on the relevant target. When the event occurs, the callback receives eventDetails, updates the status message and logs the event name and target in Developer Tools.

Use a playable video and wait for its first frame.

To test this example, put a real supported media file at the shown path. Events tied to buffering or download behavior may not fire in the same order on every connection. An unavailable sample file is not proof that your event listener is broken.

Try it in your browser

Open the page, show the Console panel, and follow this test: Use a playable video and wait for its first frame. Then change one thing in the example and observe whether the event still fires.

Common Beginner Mistakes

• Expecting loadeddata to fire without its required user action or browser condition.
• Use a playable video and wait for its first frame.
• Adding repeated event listeners without considering cleanup or unwanted side effects.

Key Takeaways

• loadeddata reports the browser loads the first media frame.
• addEventListener("loadeddata", ...) listens for the event on the appropriate target.
• Use a playable video and wait for its first frame.