TDEE calculator

what is TDEE?

TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns in 24 hours. It's the sum of your basal metabolic rate (BMR — calories spent staying alive at rest) plus everything you burn through movement, digestion, and training. If you eat at your TDEE, weight stays stable. Eat below it to cut, above it to bulk.

The standard formula is TDEE = BMR × activity factor. LiftGauge uses Mifflin-St Jeor for BMR (the most accurate among predictive equations for adults — Frankenfield et al. 2005, J Am Diet Assoc 105:775–789) and the ACSM activity multipliers below.

Mifflin-St Jeor BMR

BMR (male) = 10·kg + 6.25·cm − 5·age + 5
BMR (female) = 10·kg + 6.25·cm − 5·age − 161

Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr 1990;51(2):241–7. PMID 2305711.

activity multipliers

1.20sedentary

desk job, no steps beyond daily routine.

1.375lightly active

light movement 1–3 days/week.

1.55moderately active

training 3–5 days/week. Default for most powerlifters in a maintenance phase.

1.725active

heavy training 6–7 days/week.

1.9very active

physical job plus daily training.

ACSM Guidelines for Exercise Testing and Prescription, 11e (2022), Ch. 7. Multipliers are the Harris-Benedict revision in widespread clinical use.

cut, maintain, bulk targets

Common defaults LiftGauge uses on this page: cut = TDEE − 500 kcal (≈ 0.45 kg/wk loss via the 7700 kcal/kg constant); maintain = TDEE; bulk = TDEE + 300 kcal (≈ 0.27 kg/wk gain, biased toward lean mass).

The cut/bulk numbers are deliberately conservative. Aggressive cuts (> 700 kcal deficit) and aggressive bulks (> 500 kcal surplus) trade off against strength retention — see Helms et al. 2014 (J Int Soc Sports Nutr 11:20, PMID 24864135) and Aragon et al. 2017 ISSN Position Stand (J Int Soc Sports Nutr 14:16, PMID 28630601). For a more detailed plan with protein/fat/carb split and per-lift retention curves, use /nutrition.

limitations

Predictive equations like Mifflin-St Jeor have a measurement-error band of ±10–15 % against indirect calorimetry. Two lifters with identical kg/cm/age can have TDEEs that differ by 300 kcal/day from training history, NEAT, thyroid, sleep, and digestion alone. Use the calculator's output as a starting point: eat at the predicted target for 14 days, weigh-in 5+ times per week, and adjust ± 150 kcal if the 7-day average doesn't move as expected.

The formula also assumes a typical body composition. Very lean or very muscular lifters (FFMI > 24) are systematically under-predicted by Mifflin; Cunningham 1991 (using lean body mass) is a better fit if you know your body-fat percent. The /nutrition view shows FFMI alongside BMI to flag this.

for strength athletes

Resistance training is anaerobic and low-volume per session compared to endurance sport, so most strength-focused lifters fall in the moderately active band (1.55) even on 5-day programmes. The 1.725 band fits hybrid lifters who add 4+ hours of conditioning per week. If you're cutting for a weight class, also see strength-retention projections on /nutrition, and run your 1RM through /calculator to track training intensity at the lower bodyweight.

frequently asked

How accurate is the Mifflin-St Jeor TDEE estimate?

Within ±10 % for about 70 % of healthy adults when validated against indirect calorimetry (Frankenfield, Roth-Yousey & Compher 2005, J Am Diet Assoc 105:775–789). Outliers in both directions exist — very muscular lifters and very small or thyroid-affected individuals are most often mis-predicted. Adjust from real weight-change data after 14 days at the predicted target.

Should I use Mifflin-St Jeor or Katch-McArdle?

If you know your body-fat percent (DEXA, BodPod, or a calibrated skinfold), Katch-McArdle uses lean body mass directly and is more accurate for muscular lifters. Mifflin-St Jeor is the better default when you don't, because it relies on inputs everyone has — weight, height, age, sex — and was specifically validated against measured REE rather than fitted on athletes.

Why does my TDEE feel too low compared to other calculators?

Most consumer calculators apply a 1.6–1.8 multiplier by default, which over-states activity for a typical 3–5×/week powerlifting programme. LiftGauge uses 1.55 (moderately active) as the default for that programme volume, matching the ACSM activity bands. If you genuinely train 6+ hours per week plus a physical job, pick "active" (1.725) or "very active" (1.9).

How much of a deficit can I run while keeping strength?

Deficits below ~15 % of TDEE (roughly 350–500 kcal/day for an 80 kg lifter) preserve strength reliably in the literature, especially with protein at 2.0–2.2 g/kg (Helms 2014, PMID 24864135; Murphy & Koehler 2022 meta). Aggressive cuts (> 25 % deficit) consistently cost strength on bench and squat. The /nutrition view shows per-lift projections over 12 weeks for the same scenarios.

Does TDEE change as I lose or gain weight?

Yes. BMR scales linearly with kg in Mifflin-St Jeor, so losing 5 kg drops BMR by ~50 kcal. There's also adaptive thermogenesis — a real but smaller effect (typically 50–100 kcal/day below the linear prediction after a long cut, Rosenbaum & Leibel 2010). Re-run the calculator every 4–6 weeks or when bodyweight has shifted > 3 kg.

Should I count training calories on top of TDEE?

No. The activity multiplier already includes training. Adding training kcal a second time would double-count. The only exception is exceptional one-off output (a 5-hour hike or a meet day) — for routine training, the multiplier is the full accounting.