Contact ZwiftCalculator

This is the most valuable email I get, and the one most often sent without enough detail. Send all six of these:

• Your weight in kg, and whether that figure includes kit, shoes and bottles.
• The power you held, and whether it is average power or normalised power for the climb itself rather than the whole ride.
• The time the calculator predicted.
• The time you actually rode, taken from Zwift, ZwiftPower or your head unit rather than memory.
• Which climb: the Alpe du Zwift calculator, the Ven-Top calculator, or one of the others listed on the Zwift climbs page.
• Whether your trainer was in ERG mode or free resistance, and which trainer it is. ERG mode holds a target through the hairpins instead of letting power sag on the shallower ramps, and that alone can move a 12.2 km Alpe time by minutes.

Bike and wheel choice helps too. The Alpe estimate comes from a fitted curve, time_seconds = 148.60 × (W/kg)² - 1954.08 × (W/kg) + 8329.87, not from a physics engine simulating your frame. A regression describes what riders on the climb have actually done, so real rides that disagree with it are the only thing that can improve it. One well-documented mismatch beats ten emails saying it was way off. The regression methodology article shows how the fitting works.

Name the article, quote the sentence you are disputing, and say what you think the correct version is. Then give me something I can check: a Zwift release note, a ZwiftPower result, a course profile, a published study, or your own ride file.

Disagreement without anything checkable still gets read, but it usually ends in me asking for exactly that, so send it first. Confirmed errors get a dated correction note on the article rather than a silent edit, as set out in the editorial policy.

Likely to happen: another climb added to the climb time calculator, an extra output on a tool that already exists such as pacing splits or a target W/kg, a clearer explanation of an existing number, or a comparison like Alpe against Ven-Top extended to another pair of climbs.

Unlikely: anything needing accounts, logins, saved ride history, a live Zwift connection, or a mobile app. The site is static by design. Tell me what decision the number would help you make, not just the feature name. A request framed as “I want to know whether to attack the Alpe at 3.2 or 3.5 W/kg” is something I can build for.

Questions about the method, the data behind a calculator, or who runs the site are welcome, and I am happy to be quoted or interviewed.

To be direct about the rest: no sponsored posts, no paid links, no paid reviews, no link insertions into existing articles. That is the policy, not a starting price, so guest post pitches chasing a followed link get no reply. The site carries display advertising, kept entirely separate from what the articles say - no advertiser sees a post before it publishes or changes one after.

Use “Privacy request” as the subject line so it does not sit behind the calculator mail; the link below fills that in for you. In the body, name the right you are exercising - access, correction, deletion, objection to processing, or opt-out of sale and sharing - and give me the identifier to search on. The address you write from is normally enough.

What happens next: I confirm receipt, tell you what data actually exists, and act within the one month the GDPR allows. In most cases the honest answer is that nothing is tied to your name, because the site has no accounts, no logins and no stored calculator inputs. Where third-party analytics or advertising cookies are involved, I will name the provider and how to reach them. The privacy policy lists all of that in full.