About CalCentral

CalCentral offers free calculators that show their working. Every result comes with the formula, the steps and the sources behind it, so you can check the numbers instead of trusting a black box.

Who is behind it

Rich writes and maintains the calculators and articles.

I’m Rich, and I’ve spent 20 years working in IT, long enough to remember when “the cloud” was just weather. Over that time I’ve worked across infrastructure, support and development, a new piece of tech still gives me the same buzz it did on day one.

That curiosity spilled over into finance. Today I build Python-based systems for market research and trading, focusing on crypto and prediction markets. To me, markets are the ultimate engineering problem: noisy data, human behaviour, and no room for wishful thinking. My approach is simple: test everything, trust evidence, and respect risk.

When I’m not coding or watching markets, I’m usually planning a trip. I’ve visited more than 20 countries so far, and a few keep pulling me back. In Europe, it’s Portugal and Hungary. In Asia, Thailand and Vietnam. In North America, Toronto, Boston and New York, three cities with their own energy. Travel keeps me grounded and reminds me that the best insights often come from far outside my comfort zone.

How the calculators are built

Each calculator is a small, tested program. Before it can be published it must reproduce at least three reference cases with known results, taken from textbooks, official sources or worked examples; the formula box on each page states how many cases it is tested against. A formula is marked as reviewed only after a person has checked it against its sources.

Read more in the editorial policy. If you spot a mistake, use “Report an error” at the bottom of any page or write to contact@calcentral.org.