Attribution Reporting: updates

Review the latest changes to the Attribution Reporting API.

The Attribution Reporting proposal has changed to address community feedback, from API mechanism changes to new functionality.

Who are these updates for?

These updates are for you if:

You already are familiar with the API—for example, if you've been observing or participating in the discussions on the WICG repository and want to understand the changes made to the API.
You're using the Attribution Reporting API in a demo or in experiments.

If you're new to this API or have not experimented with it yet, read the introduction to the Attribution Reporting API.

August 9, 2023: We have begun the ramp up for the Ads Measurement and Relevance APIs, and testers can expect to see traffic levels increase over the next few days.
March 17, 2023: We've updated the status for API features.
December 15, 2022: We've published why we plan to ship the Attribution Reporting API in the first half of 2023.
June 23, 2022: Several updates have been detailed in the Attribution Reporting updates in June 2022 blog post. Additionally:
- The API handbook was updated.
- We published Experiment with Attribution Reporting: Strategy and tips for summary reports. As of July 2023, that content has been migrated to Understanding noise and Understanding aggregation keys.
March 31, 2022: New origin trial for Ads relevance and measurement APIs, which includes the Attribution Reporting API. Now completed (as of September 20, 2023).
February 7, 2022: Documentation for the header trigger redirect added.
January 27, 2022: Migration for API updates published, including:
Early 2021: Aggregate reports and view-through measurement are added to the proposal.
Early 2021: The API is renamed to "Attribution Reporting API".