Nutrition · 2 min read · Updated
What's TDEE? How many calories you really need
TDEE is the calories that keep your weight steady. Here's how it's worked out, how to use it for a cut or a bulk, and its limits.
TDEE stands for total daily energy expenditure: roughly how many calories your body burns in a day, all in. Eat about that much and your weight stays put. Eat less and you lose; eat more and you gain. Everything about cutting and bulking starts here.
How it's worked out
First comes your BMR, the calories you'd burn lying in bed all day just to stay alive. Gainsville uses the Mifflin-St Jeor equation, which uses your sex, age, height and weight and is the one dietitians lean on most. Then BMR is multiplied by an activity factor, from about 1.2 if you mostly sit up to about 1.9 if you train hard twice a day or work a physical job.
Using the number
- Maintenance: eat around your TDEE. Great for learning to lift, or a break between a cut and a bulk.
- Moderate cut: about 15 to 20% under maintenance. Gainsville shows about 18%, which usually means around half a pound to a pound a week.
- Lean bulk: about 10% over maintenance, for slow muscle gain with little extra fat.
It's a starting point
Any formula is an estimate; real people can be a few hundred calories off either way. Eat at your number for 2 to 3 weeks and watch your weekly average weight. Not moving the way you want? Move your daily number by 100 to 200 calories and check again.
The floor
Gainsville never shows a daily target under 1,200 calories for women or 1,500 for men. Going lower makes it very hard to get enough protein, vitamins and minerals, and it eats into muscle. If your maintenance is already close to that floor, the calculator won't suggest a cut at all.
Safety first: Eating far below your needs isn't a faster route; it's a riskier one. If you want to go lower than these floors, do it only with a doctor or registered dietitian.