Yes. Everything stays on your device. BangMiles stores nothing server-side except what you explicitly submit to the leaderboard — your display name and miles total only. No settings, no dates, no IP addresses. Your calculation history, anniversary date, profile name, and settings all live in your browser's localStorage and never leave your device. We have no account system and no login, so there's nothing to breach and nothing to sell. See our Privacy Policy for the full picture.

It comes from peer-reviewed research. Specifically, Levin & Wagner (2003) and a widely-cited study in the Journal of Sexual Medicine (2008) both put the average thrust count per session at around 500–600. The researchers used counters. They maintained straight faces. The results were published in an academic journal with a peer-review process. BangMiles uses 600 as the default because it's in the middle of the documented range and because "peer-reviewed" is the most impressive thing we can say about any part of this calculator. You can adjust the figure in Advanced settings if your technique is, as the tooltip says, "distinctive." We've written a full article about it: The Science Behind the 600 Thrusts Figure.

No. The calculator is a novelty. The calorie estimates use generic MET values that assume consistent activity throughout. The thrust count is an average of averages from a small set of studies. The mileage assumes perfectly consistent sessions of identical duration, frequency, and vigour across the entire period you specify. None of that is true of any real person. The number you get is a fun estimate, not a measurement. Do not present it to your GP, your partner's GP, or any legal authority.

When you use Total Since Date mode, BangMiles needs to count how many months to multiply by. Inclusive (the default) counts any month you were active in — so if your start date is 15 January and today is 10 February, that's two months. Full months only counts only completed calendar months — in that example, zero, because you haven't finished a full month between those dates. Inclusive gives more generous numbers. Full months is more conservative. Use whichever you feel represents reality more fairly. We can't help you with that decision.

Calculate your mileage on the main page. Once you have a result, a leaderboard submission form will appear at the bottom of the page. Enter a display name (e.g. "Dave & Sarah" — anything up to 32 characters) and hit Submit. We store your display name and your miles total. Nothing else. Your score will appear on the Global Leaderboard within a few seconds.

Email hello@bangmiles.com with your display name and approximate submission date. We'll remove it within 48 hours. There's no account system, so we can't automate deletion yet — it's a manual process on our end. We won't question why you want it removed.

The Odometer is the third calculation mode (the 🎉 tab). You enter a start date — typically an anniversary — and BangMiles automatically calculates your running cumulative mileage from that date to today. It updates automatically every time you visit. Save the date and it persists across sessions via localStorage. Some people find this motivating. Others find it existentially challenging. Both reactions are understandable.

Yes. BangMiles is a Progressive Web App (PWA). On iOS, open it in Safari and tap Share → Add to Home Screen. On Android, open it in Chrome and tap the Install prompt when it appears, or use the browser menu. Once installed, it opens full-screen with no browser chrome and works offline. Your data stays in localStorage — it's on-device, not in a cloud.

BangMiles compares your total against a set of reference distances: the English Channel crossing (21 miles at its narrowest), a marathon (26.2 miles), the M25 orbital motorway (117 miles), the length of mainland Britain from Land's End to John o'Groats (874 miles), New York to Los Angeles (2,790 miles), and the distance to the Moon (238,855 miles). When your total exceeds one of these, the chip lights up. We've written more about what these comparisons mean in What Does Your BangMiles Score Actually Mean?

BangMiles is a ridiculous side project, hosted by Teklan Hosting. It started as a joke calculator and became, against all reasonable expectations, a polished PWA with a global leaderboard, challenge links, an anniversary odometer, and a blog. Peer reviewed by no one. Use responsibly. Or don't.