Use Origin Trials in Microsoft Edge

You can use Origin Trials to try out experimental APIs on live sites for a limited period of time. When using Origin Trials, users of Microsoft Edge that visit your site may run code that uses experimental APIs. To access the experimental APIs on each user machine, you don't need to go to edge://flags and turn on feature flags.

For more information, see Microsoft Edge Origin Trials Developer Console. You can also provide feedback on the design of the API, your use cases, or your experience using the APIs to browser engineers and the web standard community.

Get started using Origin Trials

For more information about the experimental APIs available in Microsoft Edge, see Microsoft Edge Origin Trials Developer Console. Be sure to review the minimum version requirements for Microsoft Edge, and the trial end date, to assess the suitability of using the experimental APIs on your website.


An experiment may end earlier than planned if any of the following situations occur:

  • A major security incident.
  • If sufficient feedback is collected that indicates a major redesign is needed to meet the needs of web developers. In either case, a notification email is sent to all developers currently enrolled in the experiment.

Register for a trial of an experimental API

To register for a trial of an experimental API:

  1. Go to Microsoft Edge Origin Trials Developer Console.

  2. Click the Register button on any of the available experiments.

  3. Sign in to the Developer Console using your GitHub username and password.

  4. Click Authorize MicrosoftEdge.

  5. Complete the form.


    To enroll a single or all subdomains, choose set the Do you need to match all subdomains for the provided origin? setting to Yes. For example, is a single domain, and https://* uses a wildcard to represent all subdomains.


    The following origin formats aren't allowed.

    • Specifying a subfolder on the origin. For example,

    • Using an origin with query string parameters. For example,

  6. Click ACCEPT and REGISTER.

Apply your token

A token is instantly generated and displayed on the Microsoft Edge Origin Trials Developer Console. To begin using the trial on your website, use either of the following methods to apply the token to your page:

  • Add the origin-trial attribute value and your token to the meta tag on every page that uses the experimental API.

    <meta http-equiv="origin-trial" content="replace-with-your-token">
  • Add Origin-Trial to the HTTP response header of your server.

    Origin-Trial: replace-with-your-token


Your token is valid for 6 weeks. Before your trial ends, reminder emails are sent to you that ask for your feedback and ask you to consider renewing your trial before your token expires.

Opt out of an experiment

To opt out of an experiment, use one of the following methods to remove your token.

  • Remove the meta tag from every page that used the experimental API.

    <meta http-equiv="origin-trial" content="your-token">
  • Remove Origin-Trial from the HTTP response header of your server.

    Origin-Trial: your-token

Detect experimental features and provide a fallback

When using experimental APIs, ensure you provide a working experience to all visitors of your website. Visitors may use browsers that don't support the experimental APIs that you added to your code. Additionally, if your token expires before you renew it, the experimental API is no longer available, which may result in errors.

To avoid this situation, make sure you detect features available in your browser. For more information, see Implementing feature detection.

Roadmap for Allowed Origins

The Microsoft Edge Origin Trials portal today only supports SSL Enabled Origins, which means that websites must have HTTPS properly implemented to register for an experiment. In the future, the following secure origins are planned:

  • Register http://localhost as the origin for your experiments. To use http://localhost today, go to edge://flags and set the experiment to Enabled.

  • Use extensions with extensions:// prefixed origins to enroll in experiments.