Privacy

ReactionMetric is designed to work without an account.

Personal history

Your recent test history is stored in your browser using localStorage. It is not uploaded merely because you run the test.

Optional community benchmark

If you explicitly opt in after completing a session, the benchmark endpoint may receive the five valid trial times, false-start count, coarse device class, coarse input class, refresh-rate estimate bucket, coarse frame-stability label, a one-bit main-thread long-task flag, test version, timestamp, and a random one-session ID used to reject accidental duplicate submissions. Summary statistics are recalculated on the server from the five raw trials. The session ID is not an account ID and is not reused across sessions or sites.

What we do not ask for

We do not require your name, email address, precise location, date of birth or a user account to take the test.

Advertising and Google AdSense

ReactionMetric may use Google AdSense to display advertising. When AdSense is enabled, Google and its advertising partners may use cookies, web beacons, IP addresses, device information, or other identifiers to serve, measure, personalize, limit, or report advertising in accordance with applicable law and the user choices available in the relevant region.

Third-party vendors, including Google, may place and read cookies in your browser or use web beacons and similar technologies as a result of ads being served on this site. You can learn how Google uses information from sites and apps that use its services at Google's partner sites policy page. Where required, advertising consent choices will be presented before personalized advertising technologies are used.

ReactionMetric does not send your raw reaction-time history, benchmark trial values, name, email address, or precise location to Google AdSense for ad targeting. We do not create advertising audiences from reaction-time scores or other potentially sensitive benchmark results.

Analytics

Optional Google Analytics 4 is loaded only after you choose to accept analytics. Events that happen before consent are not sent later. If enabled, GA4 records page views and product events such as test start/completion, false starts, repeat sessions, sharing and internal navigation, with coarse test/device parameters. We do not send names, email addresses, precise location or your raw local history to GA4.

Change analytics choice

Hosting and logs

Cloudflare may process standard request metadata needed to serve and protect the site. ReactionMetric does not require an account to run the test.

Retention and deletion

Local history remains in your browser until you use the in-page “Clear local history” control for that test mode or clear site storage in your browser. Raw contributed benchmark sessions are retained for up to 24 months; a scheduled benchmark cleanup runs daily and new benchmark submissions also trigger cleanup. For benchmark/privacy requests, contact privacy@reactionmetric.com. ReactionMetric does not use the one-session benchmark ID as an account or cross-site identifier.