Who builds this
PitStopCalc is built and maintained by Alex, who spent fifteen years in semi and heavy equipment repair before writing a line of code. Every calculator here started as math done by hand in the shop — usually with somebody waiting on the number. The tools available online gave you a result with no formula and no way to check it. These show the work.
Why this site exists
Fuel cost, gearing, towing limits, and engine displacement all come down to straightforward math — but finding a calculator that shows its work, instead of just spitting out a number, is harder than it should be. PitStopCalc lays out the formula behind every result right on the page, so you can see exactly how the number was reached.
What you'll find here
Each calculator uses standard, published automotive and trucking-industry formulas — the same references a diesel tech, fleet mechanic, or gearhead would work from. Every calculator also documents its formula and answers common questions specific to that topic, right on the page.
Free, no sign-up, ad-supported
Every calculator is free to use, with no account required. The site is supported by advertising rather than subscriptions or paywalls, which is why you'll see a couple of ad placements on each page — kept clear of the calculator forms so they don't get in the way of the tool.
Accuracy first
Formulas are checked against standard industry references. That said, every result here is an estimate for planning purposes — always confirm critical figures like towing capacity, payload, and gearing against your vehicle or equipment manufacturer's specs. See the Disclaimer for details.
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Reach out any time — see the Contact page.