What are maintenance calories, and how do you find yours?
By the Bocco team · 6 min read
The short version: maintenance calories — also called TDEE (total daily energy expenditure) — are the number of calories you'd need to eat every day to keep your weight exactly where it is. Eat above it and you gain; eat below it and you lose. It's made of two pieces: your BMR (the energy your body burns just existing) times an activity multiplier (everything you do on top of that).
We'll walk through both, then a worked example so you can plug in your own numbers.
The two numbers that make up TDEE: BMR × activity
TDEE isn't one measurement — it's a calculation built from two smaller ones.
Step 1: your BMR
BMR (basal metabolic rate) is roughly what you'd burn lying in bed all day — breathing, circulating blood, keeping your organs running. The most widely used formula for estimating it is the Mifflin-St Jeor equation, derived from a 1990 study of nearly 500 people and still the equation most dietitians default to today (Mifflin et al., American Journal of Clinical Nutrition, 1990):
- Men: (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
- Women: (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
A 34-year-old woman, 65kg, 165cm: (10 × 65) + (6.25 × 165) − (5 × 34) − 161 = 650 + 1,031 − 170 − 161 = 1,350 kcal/day. That's her BMR — before she's taken a single step.
Step 2: the activity multiplier
BMR alone underestimates what you actually burn, because it ignores movement. Multiply it by a factor for how active you genuinely are (not how active you'd like to be):
| Activity level | What it actually means | Multiplier |
|---|---|---|
| Sedentary | Little to no structured exercise | 1.2 |
| Lightly active | 1–3 workouts a week | 1.375 |
| Moderately active | 3–5 workouts a week | 1.55 |
| Very active | 6+ workouts a week, or a physical job | 1.725 |
This is the step where people are least honest with themselves — "moderately active" gets picked a lot more than it's actually true. If you're not sure, round down; overestimating TDEE is the single most common reason a "calorie deficit" doesn't move the scale.
A worked example: same BMR, different TDEE
Take two people with the identical 1,350 kcal BMR from above.
- Person A works a desk job and doesn't exercise: 1,350 × 1.2 = 1,620 kcal/day maintenance.
- Person B has the same BMR but trains 4 times a week: 1,350 × 1.55 = 2,093 kcal/day maintenance.
Same body, same BMR, a 473-calorie gap in maintenance — purely from activity. This is why a generic "2,000 calories a day" guideline on a cereal box means almost nothing for any specific person: your actual number depends on your body and how you move, not a population average.
Why the number moves — and why it's an estimate, not a fact
Mifflin-St Jeor and multiplier tables are good starting points, but they're population averages, not a measurement of you. Genetics, muscle mass, sleep, and even how NEAT (non-exercise activity — fidgeting, pacing, taking stairs) fluctuates day to day can shift your real number by several hundred calories either way. The NIH's Body Weight Planner builds a similar energy-balance model and is worth trying as a second estimate if you want to cross-check.
The honest way to use a TDEE number: treat it as your starting point, not gospel. Eat at that estimate for two to three weeks, track your weight, and adjust — if you're not moving the direction you expected, nudge the number by 100–150 calories and reassess. And recalculate from scratch every time you lose or gain roughly 5kg (10lb), since a lighter body needs less energy to maintain itself.
How Bocco helps
Bocco calculates your maintenance calories from the same Mifflin-St Jeor formula the moment you finish onboarding — no spreadsheet, no separate calculator. From there it's simple: log your meals from a photo, and your daily total is compared against that target automatically. If your weight trend says the estimate is off, you adjust the target directly in Bocco rather than guessing at a new formula.
Frequently asked questions
Is TDEE the same as maintenance calories?
Yes — same number, two names. TDEE (total daily energy expenditure) is the clinical term; "maintenance calories" is what most people actually search for and say out loud.
How accurate is a TDEE calculator?
It's a ballpark, not an exact reading. Formulas like Mifflin-St Jeor are typically within about 10% of measured energy expenditure for most people — close enough to start from, but only watching the scale over a few weeks confirms your real number.
Does TDEE change over time?
Yes. It drops as you lose weight (a lighter body needs less energy to maintain) and shifts whenever your activity level genuinely changes. Recalculate every 5–10kg (10–20lb) of change, not just once at the start.
What's the difference between BMR and TDEE?
BMR is just the energy your body burns at rest — no movement included. TDEE is BMR plus everything else: walking, workouts, digestion, even fidgeting. TDEE is always the bigger number.