Calorie Calculator

What is the Calorie Calculator?

Estimate daily calories to maintain your weight, with gentle targets for gradual loss or gain. Calorie needs vary with age, sex, size and activity, and this calculator turns those into a maintenance figure plus gentle targets for gradual change.

How to use the Calorie Calculator

1. Enter your sex, your age, your weight, your height and the remaining fields.
2. Results update automatically as you type; you can also press Calculate.
3. Read the output: maintain weight, gradual loss (≈0.25 kg/week), gradual gain (≈0.25 kg/week).
4. Use the 📊 chart to see the result visually, then copy or share it.

Formula and method

Worked example

With sex = Female, age = 30 years, weight = 65 kg, height = 165 cm, activity level = Light (1–3 days/week), the Calorie Calculator returns maintain weight: 1,884 kcal/day; gradual loss (≈0.25 kg/week): 1,609 kcal/day; gradual gain (≈0.25 kg/week): 2,159 kcal/day.

Where the Calorie Calculator helps in real life

You want to lose a few kilograms before a summer wedding without crash dieting. The calculator suggests a modest daily deficit, which supports steady loss you can keep up while still having energy for work and exercise.

You started training for a half marathon and feel drained on long-run days. Comparing what you eat with the maintenance figure for a more active level may reveal you are under-fuelling.

Common mistakes to avoid

• Choosing an activity level based on your best week rather than a typical one.
• Setting a very large deficit that leads to fatigue and rebound eating.
• Leaving drinks, sauces and snacks out of your food log.
• Expecting the scale to move by the same amount every day.

💡 Practical tip: After three or four weeks, adjust your target based on what your weight trend actually did — the formula is only a starting estimate.

Tips for better results

• Compare your weekly average weight rather than single weigh-ins.
• Prioritize protein and high-fibre foods when eating less, to stay fuller.
• Speak with a doctor or dietitian before making large changes to your diet.

⚠️ This tool provides general information and is not medical advice. It is not a substitute for diagnosis or treatment by a qualified healthcare professional.

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