Client Calorie Calculator
Built for setting a client up rather than for personal use: pick the phase and the rate, and it produces the prescription plus the reference numbers you will want in the conversation.
Your results
An estimate to start from, not a prescription to defend. The only reliable maintenance figure comes from two weeks of the client's own weight data. Within a personal trainer's scope: general healthy eating guidance, protein and calorie targets, and helping a client interpret their own tracking. Outside it: bespoke prescriptive meal plans, and anything involving a medical condition — those need a registered nutrition professional. Knowing where that line sits protects you and your client.
How to use this with a client
- Set the phase and the rate first, in conversation. The rate is the decision that matters most, and it is the one clients want to push.
- Treat the output as a starting hypothesis. Any equation is within about 10% for most people — on a 2,400 kcal maintenance that is 240 kcal, larger than many intended deficits.
- Get two weeks of data, then correct. Track intake and daily weight, compare week one's average with week two's, and adjust by 100–150 kcal.
- Recalculate every 5 kg. Maintenance falls roughly 20–25 kcal per kg lost.
- Set the expectation out loud. Say the real timeline, warn about the scale behaving strangely in the first fortnight, and name which measures you will actually be watching.
Why the rate is capped
If the chosen rate would push intake below 1,200 kcal for a woman or 1,500 for a man, the figure shown is held at that floor and flagged.
That is deliberate. This is a tool a coach may hand to a client, and displaying a 600 kcal prescription with a warning attached is worse than not displaying it — warnings get skipped and numbers get used.
If a client wants faster loss than the floor allows, the honest answer is that the rate is the wrong lever. Add daily walking instead of cutting further: it costs no recovery capacity, it does not drive hunger the way hard cardio does, and it addresses the real cause of most stalls — spontaneous movement falling as the deficit continues.
Common questions
What rate should I set for a client?
0.5–1.0% of body weight per week for fat loss; 0.25–0.5% for muscle gain. Beginners at the top of the gain range, experienced lifters at the bottom.
Should I use an equation or measure maintenance?
Start with the equation, then measure. Two weeks of tracking plus daily weigh-ins gives a number no calculator can.
Can I write my client a meal plan from this?
Calorie and protein targets are within a trainer's scope. A bespoke prescriptive meal plan is not — that needs a registered nutrition professional.
How often should I adjust?
On three weeks of data, by 100–150 kcal, and never on a single week.
Related calculators
Track the numbers, not just calculate them
MyFitsy stores your weight, measurements and every session, so the figures above become a trend instead of a one-off.
