01Calculators
Four numbers to start from.
BMI, energy needs, macro split and hydration — all calculated in your browser, none of it sent anywhere. Switch between metric and imperial at the top.
These are estimates. BMI cannot distinguish muscle from fat and reads high for most strength athletes. Energy formulas carry roughly ±10% error before you account for how you actually live. None of this is medical advice — if you are pregnant, managing a health condition or have been away from training for a long time, speak to a GP first. Members get a DEXA scan and a lactate-guided zone test, which answer these questions properly.
02The reasoning
Where these
numbers come from.
Four notes on the maths, written by Elena and Nadia.
It was designed in the 1830s to describe populations, not people. It is a useful screening number and a terrible individual verdict — a 95 kg rugby second row and a 95 kg sedentary office worker of the same height get the same score. Use it as one input, then measure something better.
It is the equation with the best average accuracy across a general adult population, which is why the British Dietetic Association reaches for it. Harris–Benedict overestimates for most people; Katch–McArdle is better but needs a body-fat figure you probably do not have yet.
Do not chase it to the kilocalorie. Eat around it for two weeks, weigh yourself on four mornings a week, and adjust by 150 kcal based on what the average does. The number is a starting point; the trend is the data.
1.6 g per kilogram is where the benefit curve flattens for most people, and 2.2 g is where it is genuinely flat. Above that you are just buying expensive urine. Spread it across three or four meals.
Membership open — Shoreditch, Wharf, Chelsea
Estimates are fine. Measurement is better.
A DEXA scan and a lactate-guided zone test are included from Premium, and £95 and £140 as one-offs.
Prefer to talk? +44 20 7946 0318 · Mon – Fri, 07:00 – 20:00