Nutrition tool
Calorie calculator
Find out how many calories you burn in a day, and what to eat to lose fat or gain muscle.
Want this done for you, every session?
FitJur tracks what you eat against this target, scans barcodes, and adjusts the number as your weight changes.
How it works
The calculator starts with the calories your body burns at rest, using the Mifflin-St Jeor equation, which is the one most dietitians use. It then multiplies by your activity level to get your daily total.
The fat-loss target is 500 calories under maintenance, which is about half a kilo a week. The muscle-gain target is 300 over, enough to grow without adding much fat. These are the same targets FitJur sets in the app.
Every calculator is an estimate. Eat at the number for two weeks, weigh yourself in the mornings, and adjust by 100 to 200 calories if the scale is not moving the way you want.
Which activity level are you?
Most lifters overestimate this. If you train four days a week and sit the rest of the time, pick the middle option.
Desk job, little exercise
Mostly sitting, no regular training.
Train 1–3 days a week
A few sessions a week or an active hobby.
Train 3–5 days a week
Regular lifting or sport most days. Most people who use this page.
Train 6–7 days a week
Training almost every day, or two-a-days some days.
Hard training plus a physical job
Training hard every day on top of a job on your feet.
Questions
How accurate is this?
Usually within 10 percent. Your real number depends on muscle mass, how much you move outside training, and genetics. Two weeks of tracking your weight tells you more than any formula.
Should I eat the same on rest days?
You can. The activity level already averages your training across the week. Some people prefer eating a little more on training days and less on rest days, and both work if the weekly total is the same.
How fast should I lose weight?
Half a kilo, or about one pound, a week keeps most of your muscle. Faster than one percent of bodyweight a week and you start losing strength.
More tools
- One-rep max calculator Estimate your 1RM from any set, with training loads for 1 to 12 reps.
- Plate calculator Type the weight, see which plates go on each side of the bar.
- Warm-up sets calculator Your working weight in, a warm-up ramp out.
- 5/3/1 calculator Your max in, the training max and all four weeks of the cycle out.
- DOTS and Wilks calculator Compare your total across bodyweights with the scores powerlifting uses.
- Protein calculator How much protein to eat a day for your weight and goal.
- Macro calculator Turn a calorie target into grams of protein, carbs and fat.