Methodology
Every value on this site is one database row with three required fields: the URL of the airport's or operator's own page, a quote of 25 words or fewer copied from that page, and the date we last checked it. The rules below are enforced by code, not by editors.
1. Where a value may come from
- Official: the airport's own domain (heathrow.com, gatwickairport.com, manchesterairport.co.uk and so on). Only these pages may be marked official.
- Operator: the transport operator's own page (Heathrow Express, Transport for London, TransPennine Express) for first and last train times.
- Secondary: anything else. A secondary value may display, but it never counts towards publishing a page.
2. When a page exists at all
An airport × topic page publishes only when it holds at least 3 official or operator values. Below that, the address returns a real 404 rather than a thin page. Titles and headings come from one template per topic and never contain a price.
3. Three checks on every value
- Verbatim quote. The 25-word quote must appear word for word on the source page when we fetch it ourselves. A paraphrase is rejected.
- Domain matches confidence. A value marked official whose source is not the airport's own domain is rejected.
- Plausible range and cross-field checks. A drop-off charge above £200, a free period above 24 hours, or a car park's free period filed as the forecourt's free minutes is held for a person to read.
4. Freshness
Each value shows Source: host · Verified date. A value older than 60 days carries a "check with the airport" badge. A daily job fetches a sample of live pages and confirms the rendered value still matches the database; a refresh job re-reads source pages and records any changed figure in the change log, with the old and new values.
5. Worked example, computed live
From the 21 UK airports with a published drop-off charge on file as of 4 September 2026: 21 charge and 0 are free. The median charge is £7, the mean £7.1; the range runs from £4 (Belfast City Airport) to £10 (London Gatwick, London Stansted). 43% charge £8 or more.
These figures are produced by the same function the site's monthly data job runs (`computeNumbers` in the repository); nothing on this page is typed by hand, so the numbers move when the facts do. Newest verification 3 September 2026, oldest 3 September 2026.
6. Data sources
- Airport websites (drop-off, pick-up, parking and facilities pages), fetched with a browser because six UK airports block plain requests.
- Rail operator timetable pages for first and last trains.
- Search demand figures from DataForSEO, recorded with the pull date and location, used only to decide whether a page is worth building.
- Google Search Console and PageSpeed Insights for monitoring what is live, never as a source of facts.
7. What this site refuses to do
- State a figure from memory, an estimate, or a third-party guide. If the airport does not publish it, the row does not exist.
- Overwrite a checked value automatically. A changed figure is proposed for a person to read against the source page.
- Publish prose beyond a 60-word topic introduction. The pages are tables of sourced values.
- Pad a page with secondary sources to cross the 3-value publishing line.
Corrections: every page names its source; if a value is wrong, the source page is what changed. Contact details are in the site footer.