What is stored
A saved record contains a random local record ID, test type, creation time, duration, language, optional label and input mode, protocol version, summary metrics, and session-quality flags. It does not store raw wheel-event logs by default, a device serial number, screen coordinates, IP address, or a cross-site identity.
Each test type keeps up to 20 records and the site keeps up to 100 records in total. Oldest records are removed when a limit is exceeded. A migrated legacy speed summary is marked with its legacy protocol so it is not silently presented as a current controlled run.
Comparison boundaries
Before two records are compared, the manager checks test type, protocol version, duration, direction mode, delta mode, and serious quality flags. Different delta units can still permit a review of metrics that do not depend on raw delta, but raw totals are excluded. An incompatibility is explained instead of being forced into a winner.
A personal baseline is only a local bookmark for one test type. It is not a global average, percentile, recommendation, or performance standard.
Privacy and control
JSON, CSV, and print views are created in this browser after you request them. Local labels are excluded from downloads unless you choose to include them. Other people who use the same browser profile may see saved records, so clear them when using a shared device.
If localStorage is blocked or unavailable, the tools continue with in-memory results where possible and show a warning. Closing or refreshing the page can remove that fallback data. Clearing browser site data also removes saved summaries and baselines.