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LearnGet Started💡 Origin Trials Registration

WebNN Origin Trials Registration

The Web Neural Network API (WebNN) is now available for testing through Origin Trials on Chrome and Edge browsers. Origin Trials allow developers to experiment with new web platform features in production environments before they become standard.

What is an Origin Trial?

An Origin Trial gives you access to experimental features for your origin, allowing real users to interact with the new functionality. This helps browser vendors gather feedback and validate features before making them available to all users.

Prerequisites

Before registering for the WebNN Origin Trial, ensure you have:

  • A website or web application that will use the WebNN API
  • Administrative access to modify HTTP headers or HTML on your site
  • A valid origin (protocol + hostname + port)

Registration Steps

For Google Chrome

  1. Navigate to the Chrome Origin Trials page

    Visit the WebNN Chrome Origin Trial registration page 

  2. Sign in with your Google account

    You’ll need to authenticate to register for the trial

  3. Provide your origin

    Enter the origin where you plan to use WebNN (e.g., https://example.com)

    • The origin must include the protocol (https://)
    • Wildcards are supported for subdomains (e.g., https://*.example.com)

  4. Submit your registration

    Review and accept the terms, then submit your registration

  5. Receive your trial token

    You’ll receive a unique token for your origin

For Microsoft Edge

  1. Navigate to the Edge Origin Trials page

    Visit the WebNN Edge Origin Trial registration page 

  2. Sign in

    Authenticate to access the trial registration

  3. Provide your origin

    Enter the origin where you plan to use WebNN

  4. Submit your registration

    Accept the terms and complete your registration

  5. Receive your trial token

    You’ll receive a unique token for your origin

Implementing the Trial Token

Once you’ve received your trial token, you need to add it to your website. There are three methods:

Method 1: Meta Tag

Add a meta tag to the <head> section of your HTML:

<meta http-equiv="origin-trial" content="YOUR_TOKEN_HERE">

You can insert both meta tags into the <head> section of HTML document, one for each browser’s token. The browsers are designed to ignore tokens they don’t understand, so you can safely include both.

This method is useful when you cannot modify server headers.

Method 2: HTTP Header

Add the token as an HTTP response header:

Origin-Trial: YOUR_TOKEN_HERE

This method applies the token to all resources served from your origin.

Method 3: Provide a token programmatically

Inject a token with JavaScript:

const otMeta = document.createElement('meta');
otMeta.httpEquiv = 'origin-trial';
otMeta.content = 'TOKEN_GOES_HERE';
document.head.append(otMeta);

Verifying Your Setup

To confirm the Origin Trial is active:

  1. Open your website in Chrome or Edge
  2. Open DevTools (F12)
  3. Navigate to the Console tab
  4. Check for any Origin Trial related messages
  5. Verify that navigator.ml is available:
if ('ml' in navigator) {
  console.log('WebNN API is available');
} else {
  console.log('WebNN API is not available');
}

Key Considerations

Trial Duration

  • Origin Trials have a limited duration
  • Monitor the trial status on the respective browser’s Origin Trials page
  • Plan to remove or update tokens when the trial ends

Browser Support

  • Chrome: 146 to 148
  • Edge: 146 to 148
  • The feature is experimental and subject to change

User Opt-Out

  • Users can disable Origin Trials in their browser settings
  • Your code should gracefully handle cases where WebNN is unavailable

Origin Trial Feedback

As a trial participant, your feedback is valuable and helps shape the future of the WebNN API:

  • Submit feedback through the origin trial site: You can provide private feedback directly through the Chrome Origin Trials dashboard. This feedback is confidential and only available to a limited group of people on the Chrome team.
  • Public community feedback 

Token Renewal

  • When your trial token approaches expiration, you will receive an email notification with a renewal link
  • To renew your token, you will be asked to submit feedback about your experience with the trial
  • This feedback helps browser vendors understand how the feature is being used and what improvements are needed

Example Usage

Once the Origin Trial is active, you can begin using the WebNN API:

async function initializeWebNN() {
  if (!('ml' in navigator)) {
    console.error('WebNN is not supported');
    return;
  }
 
  try {
    const context = await navigator.ml.createContext();
    // Your WebNN implementation here
  } catch (error) {
    console.error('Failed to create WebNN context:', error);
  }
}
 
initializeWebNN();

Best Practices

  1. Feature Detection: Always check for WebNN support before using the API
  2. Fallback Strategy: Implement fallbacks for browsers without WebNN support
  3. Error Handling: Handle errors gracefully as the API is experimental
  4. Performance Monitoring: Track performance improvements from WebNN usage
  5. Security: Only use Origin Trials on HTTPS origins

Getting Help

Next Steps

After registering and implementing the trial token:

  1. Test your WebNN implementation thoroughly
  2. Monitor performance and user experience
  3. Provide feedback to browser vendors
  4. Stay informed about trial expiration dates
  5. Plan for migration to the standard API when available

Additional Resources

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