How many calories should I eat on Mounjaro or Wegovy? See maintenance, a safer weight-loss range, plus protein and fibre targets.
Maintenance calories
2100
BMR ~1527 kcal × activity
Weight-loss calories (approx.)
1600
~500 kcal below maintenance (floored)
Protein target
104g
Range 96–112g
Fibre target
25g
Helps with GLP-1 constipation risk
Maintenance uses Mifflin–St Jeor × activity. Weight-loss calories subtract ~500 kcal (floored so intake is not extremely low). Protein and fibre targets support muscle and constipation risk on GLP-1s — educational only, not a prescription. On Mounjaro or Wegovy, appetite often drops below these numbers — use them as a floor to protect energy and muscle, not a crash-diet target.
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Suggested citation: GLP-1 Calorie Calculator — www.glppal.app/tools/calorie-calculator
Unlike generic “lose weight” tools, this calculator answers “how many calories should I eat on Mounjaro?” with a maintenance estimate, a moderate ~500 kcal deficit and floors that discourage extreme restriction. Appetite on GLP-1s can fall below these numbers — the goal is protecting energy, muscle and regularity, not celebrating under-eating.
Choose metric or imperial units.
Enter weight, height, age, sex and activity.
Review maintenance, weight-loss calories, protein and fibre.
Pair with the meal planner if you need food ideas that fit a low appetite.
There is no single number. Clinical weight-loss trials often use about a 500 kcal daily deficit from maintenance. Many adults land roughly in the 1,200–1,800 kcal range depending on size and sex — but consistently eating far below that can worsen fatigue, constipation and muscle loss.
Download on the App Store. Log injections, appetite, weight and side effects — with reminders and weekly pattern insights.
GLPPal is designed for tracking and educational purposes only and is not medical advice.