How to Set Calorie Targets
Setting a calorie target is estimate, test, adjust. Most people do the estimate and skip the other two, then blame the calculator.
Last updated: 1 July 2026
Overview
A calorie target is a hypothesis you test against the scale, not a number handed down by a website.
Every calculator uses a population average equation. Individual metabolic rate varies by several hundred calories around that average, and daily movement varies by more. Your calculator number will be in the right area and rarely exactly right.
Quick Answer
To set a calorie target, estimate maintenance from bodyweight and activity level, then adjust for your goal: subtract 15 to 25 percent for fat loss, add 5 to 15 percent for muscle gain, or stay level for maintenance. Track for two weeks and adjust based on actual weight change.
Key Points
- Calculators give a starting point, not an answer.
- Two weeks of weight data beats any equation.
- Fat loss: 15 to 25 percent below maintenance.
- Muscle gain: 5 to 15 percent above.
- Adjust one thing at a time, then wait.
Step one: estimate maintenance
The quick method, accurate enough to start:
| Activity level | Calories per kg bodyweight |
|---|---|
| Desk job, little movement | 28 to 30 |
| Desk job plus 3 gym sessions | 30 to 33 |
| Active job or 5 training days | 33 to 37 |
| Physical job plus training | 38 to 42 |
A 70kg person with a desk job and three gym sessions: roughly 2100 to 2300 calories.
The better method, if you have two weeks: log everything you normally eat without changing anything. If your weight held steady, that average is your maintenance. That number beats every equation because it is measured rather than predicted.
Step two: adjust for your goal
| Goal | Adjustment | For 2200 maintenance |
|---|---|---|
| Fat loss, moderate | Minus 20 percent | 1760 |
| Fat loss, conservative | Minus 12 percent | 1935 |
| Maintenance | None | 2200 |
| Muscle gain, lean | Plus 8 percent | 2375 |
| Muscle gain, faster | Plus 15 percent | 2530 |
Larger surpluses do not build muscle faster past a point. They add fat, which you then spend months removing.
Step three: test and adjust
Weigh yourself daily under the same conditions and use a seven day average. Compare this week's average to last week's.
| Goal | Expected weekly change |
|---|---|
| Fat loss | Minus 0.5 to 1 percent of bodyweight |
| Maintenance | Within 0.3 percent either way |
| Muscle gain | Plus 0.25 to 0.5 percent of bodyweight |
| Two week result | Adjustment |
|---|---|
| On target | Nothing |
| Losing too slowly | Minus 100 to 150 calories, or add daily steps |
| Losing too quickly | Plus 100 to 150 calories |
| Gaining too quickly | Minus 100 to 150 calories |
Change one variable, wait two weeks, look again. Adjusting weekly generates noise.
Why calculators disagree
Different calculators use different equations, different activity multipliers and different assumptions about body composition. A 400 calorie spread between two calculators for the same person is completely normal.
That is not a reason to distrust all of them. It is a reason to treat any single one as a starting estimate.
Common Mistakes
| Mistake | Why it causes problems | Better approach |
|---|---|---|
| Picking the calculator with the nicest number | Sets an unrealistic starting point | Use a middling estimate and test |
| Choosing an inflated activity level | Overestimates maintenance badly | Be honest, most people are less active than they think |
| Adjusting every few days | Noise, not signal | Two week windows |
| Eating back exercise calories | Trackers overestimate burn substantially | Set a target and leave it |
| Changing calories and steps at once | Cannot tell what worked | One change at a time |
Frequently Asked Questions
How accurate are calorie calculators?
They are typically within about 10 percent for most people, which can still be 200 to 300 calories out. Treat the output as a starting point.
Should I eat more on training days?
You can, and it is a reasonable refinement, but a consistent daily target is simpler and works just as well for most people.
What if I am not losing weight on 1500 calories?
Almost always the logging is incomplete rather than the metabolism unusual. Weigh food for a week, including oils, drinks and weekends, before concluding anything.
Do I need to count calories forever?
No. Many people count for a few months to learn portion sizes, then move to less formal tracking once the habits are established.
Sources
NHS eatwell guide - https://www.nhs.uk/live-well/eat-well/
British Nutrition Foundation - https://www.nutrition.org.uk/