How we check data

Last updated: 2026-10-15

Sources, in order of trust

• Official: the published race calendar, circuit and organiser websites, official price lists.
• Public data: NOAA weather station records (public domain), Wikidata (CC0), European Central Bank and central bank exchange rates.
• Fan travel guides: used only when official pages are silent; such facts are marked medium or low confidence and shown as estimates.

How we collect

• We read each site's robots.txt and terms of use first and skip sites that do not allow automated reading. Ticket shops run by third parties are never crawled; we only link to them.
• We fetch at most one page per second per site, keep a copy so we never fetch a page twice, and never log in.
• Facts are rewritten in our own words. We never copy text from other websites.

How we keep it honest

• Every value stores its source and the date checked; pages show "Last checked".
• Gaps are left blank and marked "to verify".
• Where sources disagree, the official source wins and the difference is logged.
• An automatic check blocks publishing if a price has no source, a date is outside the season, or a disclaimer is missing.
• Prices for upcoming races are re-checked 8 weeks, 4 weeks and 1 week before the race weekend. Changes are logged with the old and new value side by side.

Weather

Race-month weather is the average of daily readings over the last 10 complete years at the nearest suitable weather station (named on each page). "Rain" means the share of days with at least 1 mm of rain.