Report an Error

Every figure on this site traces back to a published source, and every report is checked against that source by me personally. To make the check fast, it helps to include four things. First, the page URL — the exact page where the problem is, copied from your address bar. Second, the number you got: what you entered into the calculator, and the result it gave you, exactly as it appeared. Third, what you expected: the result you believe is right, and — if you have it — where that figure comes from, such as a published table, a governing-body document or your own hand calculation. Fourth, any details that might matter: the units you were using (metres or yards), the pool course, and the stroke or event if the page asked for one. Most apparent errors turn out to be a units mix-up, which is exactly why the details help — and when a report is a genuine error in the site's data or code, it gets fixed, the affected pages are re-checked, and the correction is dated, as the editorial policy describes.

One more thing that helps: if the wrong number came from a worked example on the page rather than from the calculator itself, say so in your report. Examples and live code are checked separately, and knowing which one you were reading tells me exactly where to look first.

The form below composes an email in your own mail app — this site has no server to send it to, and nothing leaves your device until you press send in your app. If you would rather write a plain email, send the same details to ianwelkins@gmail.com.