Maintenance is the calorie number where your weight stays put. Every other target is built from it — a deficit is maintenance minus something, a surplus is maintenance plus something — which makes it the most useful number in nutrition and the one people most often have wrong.
The short answer
For most adults, maintenance lands somewhere between 28 and 34 calories per kilogram of body weight, depending on how much you move. At 70 kg that's roughly 1,960–2,380 a day.
That range is wide on purpose. It's a starting point, not an answer.
Rest days
1,829kcal
A gentle deficit for steady fat loss. Training adds about 315 kcal on the days you do it — so the two numbers differ, as they should.
The calculator does the more careful version: it estimates what your body burns at rest from your age, height, weight and sex, scales that for how much you move on an ordinary day, then adds your training separately. You get a rest-day number and a training-day number, because those two days genuinely aren't the same and averaging them leaves you slightly under-fuelled when you train and slightly over-fed when you don't.
Why the formula is only a starting point
Every calculator on the internet, this one included, is running an equation fitted to a population. You are one person, and the equation has never met you.
The gap is real and it is not small. Two people matched on age, height, weight and sex can differ by several hundred calories a day. The reasons are mundane — how much you fidget, how much you actually walk versus how much you think you walk, how hard your sessions really are, what your thyroid is doing, how much muscle you carry. None of that is in the formula, because none of it can be.
So the honest framing is: the formula gives you a hypothesis. The scale gives you the answer.
How to find your real maintenance
You measure it. It takes about three weeks and it is genuinely simple:
- Eat around the estimate. Take the calculator's maintenance number and eat close to it. Don't chase precision — close is fine.
- Weigh yourself most mornings. Same conditions: after the bathroom, before food, minimal clothing. Daily weight swings by a kilo or more for reasons that have nothing to do with fat, so you are not reading any single morning.
- Compare week to week, not day to day. Average your weigh-ins for week one. Do the same for week three. The difference between those two averages is your signal.
- Adjust. If the average went up by about half a kilo across the fortnight, you were eating roughly 250 calories a day above maintenance — drop by that much. If it went down by the same, add it. If it barely moved, you've found your number.
That arithmetic works because a kilogram of body weight change reflects roughly 7,700 calories of surplus or deficit. Half a kilo over fourteen days is about 3,850 calories, or 275 a day. You don't need to be exact; you need to be pointed the right way.
Three weeks, not three days
The single most common mistake is judging maintenance on a few days. Water shifts with your carbs, your salt, your sleep and — if you have a menstrual cycle — the week you're in. Those swings are larger than the fat change you're trying to detect. Give it three weeks and the noise averages out.
Your maintenance is not a fixed number
Once you have it, it will move. That's normal, not a betrayal:
- You get lighter. A smaller body costs less to run. Lose 10 kg and your maintenance falls by roughly 150–250 calories a day, purely because there's less of you.
- You move less than you think you do. In a prolonged deficit, unconscious movement drops — you take the lift, you fidget less, you're slower around the house. This is real and it is not a character flaw.
- You gain muscle. Muscle costs more to maintain than fat, though the effect is smaller than the internet suggests.
- Seasons change. A winter of short walks burns less than a summer of long ones.
Which is why maintenance is better treated as something you keep measuring than something you calculate once. The number you found in January is a fair guess for March and a poor one for September.
What it feels like when you've got it right
Weight holds steady inside a band of about a kilo or two, and drifts within that band rather than trending. You aren't hungry all the time. You aren't forcing food down. Your training doesn't feel harder week over week. Nothing dramatic happens — which is precisely the point, and precisely why maintenance is hard to stay motivated for.
If that sounds unremarkable, it's worth saying plainly: being able to hold your weight on purpose is the skill that decides whether a fat-loss phase lasts. Anyone can lose weight for eight weeks. Holding the result is the part most people never learn, because they were never taught what maintenance is or how to find it.
Let Sophia measure it for you
The four-step method above works, and it is also four weeks of arithmetic you have to remember to do. Sophia does it in the background. She starts from the same formula everyone else uses, tells you plainly that it's an estimate, and then watches what actually happens to your weight against what you actually ate. Around week three she replaces the estimate with a number measured from you — and keeps re-measuring it as your weight, your training and your life change.
You'll know when she does, because she'll say so, and she'll show you the arithmetic if you ask.