From the blog
Long-form guides that explain the calculations behind everyday decisions: what the formula actually does, how to read the result, and where the number stops being useful. Each article links to the tool that runs the maths for you.
The arithmetic of a calorie deficit is simple and the estimates feeding it are not. Here is how BMR and TDEE are calculated, how wrong they can be, and how to set a target that survives contact with reality.
Three years into a 30-year mortgage, most borrowers are surprised by how little they owe less. Nothing is wrong — that is exactly what the amortisation formula does, and understanding it changes how you pay.
The advice to add a capital letter and a symbol is a leftover from the 1980s. What defeats a modern cracking rig is entropy — and entropy comes overwhelmingly from length.
Most conversion factors you half-remember are approximations. A few are exact by international definition. Knowing which is which — and three mental shortcuts — covers almost every everyday conversion.
BMI was invented to describe populations, not people. It is still useful — as long as you know exactly what it is blind to. Here is what the number means and what to measure alongside it.
The formula is four symbols long, yet almost everyone underestimates what it does over twenty years. Here is compound interest without the mysticism: how it works, what each term means, and where intuition fails.