What determines how many calories you should eat?
There is no single calorie target that works for everyone. The right number depends on:
- Age — calorie needs often change over time
- Sex — baseline needs often differ
- Height and weight — larger bodies generally burn more energy at rest and in motion
- Activity level — training, walking, and daily movement all add up
- Goal speed — faster loss usually means a larger deficit (and often a harder plan)
That is why generic advice like “eat 1,200 calories” often misfires. Weight loss tends to work better when the target is based on your maintenance estimate, not a random number.
What is a calorie deficit?
A calorie deficit means eating fewer calories than your body burns in a day. If your body uses 2,300 calories and you eat 1,900, your deficit is 400 calories.
Over time, a consistent deficit can lead to weight loss. A smaller deficit is often easier to maintain; a larger deficit may feel faster on paper but harder to stick with.
How to estimate your calorie target for weight loss
Step 1: Estimate maintenance calories
Maintenance calories are often called TDEE (total daily energy expenditure)—everything you burn from basic body functions, digestion, movement, and exercise. Try the
TDEE calculator for a starting estimate.
Step 2: Subtract a realistic deficit
Once you have an estimated maintenance number, subtract a deficit you can sustain:
- 250 calories/day — slower, often easier
- 500 calories/day — a common moderate cut
- 750 calories/day — more aggressive; not for everyone
Example: If maintenance is about 2,400 kcal/day, eating about 1,900 kcal/day is roughly a 500 kcal deficit.
How fast will you lose weight?
A deficit of about 500 kcal/day is often described as roughly 0.5 kg or ~1 lb per week on paper. In real life, water shifts, adherence, tracking accuracy, sleep, stress, and activity all move the scale week to week.
The goal is usually a plan you can follow long enough to see a trend—not the fastest possible number on day one.
What is a safe calorie deficit?
For many healthy adults, a moderate deficit is a practical starting point. Very low targets can be harder to sustain and may affect energy, training, and how you feel day to day.
If you have a medical condition, take medications, are pregnant, or have a history of disordered eating, talk to a qualified professional before changing how you eat.
Common mistakes
- Picking a target that is too low to sustain
- Ignoring activity and using a one-size-fits-all number
- Assuming one high-calorie day “ruins” everything (weekly averages matter)
- Under-eating protein while trying to lose fat
- Changing calories every few days instead of evaluating trends over 2–3 weeks
Should you track macros too?
You do not have to track macros to lose weight; calories drive weight change. Protein can still help with fullness and supporting lean mass during a deficit—see the
macro calculator if you want targets.
Many people use food logging apps for consistency. For example,
MyFitnessPal
is a popular option (third-party site; not affiliated with LeanCalc).
Use LeanCalc for your numbers
The free deficit calculator can help you estimate:
- Maintenance calories
- A daily calorie target with your chosen deficit
- Protein, carbs, and fat in one pass
- A simple 12-week projection to set expectations
Open the LeanCalc calorie deficit calculator
Frequently asked questions
How many calories should a woman eat to lose weight?
It depends on height, weight, age, and activity. A maintenance estimate minus a moderate deficit is usually more useful than a fixed number like “1,200.”
How many calories should a man eat to lose weight?
Same idea—use your stats. Many men maintain at a higher intake than many women, so loss targets are often higher too, but individual variation is large.
Is a 500 calorie deficit enough?
For many people it is a reasonable place to start. Adjust based on real progress, hunger, and energy—not only the scale.
Can you lose weight without exercise?
Yes. A sustained deficit is the main lever for weight loss; exercise adds health and can increase how much you can eat while still in a deficit.