Calculator Inputs
Use current body measures and your usual weekly activity. Add a manual calorie adjustment only when your clinician has given one.
Example Data Table
These examples show how the estimate changes with activity, trimester, and body size. Values are rounded to the nearest calorie.
| Age | Height | Weight | Activity | Trimester | Base TDEE | Adjustment | Estimated Pregnancy TDEE |
|---|---|---|---|---|---|---|---|
| 30 | 165 cm | 68 kg | Lightly active | Second | 1,925 kcal | 340 kcal | 2,265 kcal |
| 28 | 170 cm | 75 kg | Moderately active | Third | 2,343 kcal | 452 kcal | 2,795 kcal |
| 34 | 160 cm | 60 kg | Sedentary | First | 1,523 kcal | 0 kcal | 1,523 kcal |
Formula Used
The calculator first estimates resting metabolism with the Mifflin-St Jeor equation for adult women, then multiplies that result by an activity factor to estimate daily maintenance energy.
Resting metabolic rate: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
Base TDEE: Base TDEE = BMR × activity factor
Pregnancy adjustment: First trimester = 0 kcal, second trimester = 340 kcal, third trimester = 452 kcal
Final estimate: Pregnancy TDEE = Base TDEE + pregnancy adjustment or clinician-provided manual adjustment
For multiple pregnancy, the calculator adds 300 kcal for each additional fetus as a rough planning estimate. That situation often needs individualized medical nutrition guidance.
How to Use This Calculator
- Choose metric or imperial units.
- Enter current weight, height, and age.
- Select the activity level that matches your real week.
- Choose your trimester, or enter pregnancy week for automatic trimester selection.
- Set the number of fetuses when carrying multiples.
- Add a manual calorie adjustment only if a clinician gave one.
- Choose how many eating occasions you plan daily.
- Press calculate to see TDEE, base maintenance, adjustment, and average calories per eating occasion.
- Use the CSV or PDF buttons to save the current estimate.
Frequently Asked Questions
1) What does pregnancy TDEE mean?
Pregnancy TDEE means total daily energy expenditure during pregnancy. It estimates how many calories you may need each day after combining resting metabolism, daily movement, and pregnancy-related energy demands.
2) Why does the first trimester add no default calories?
Many guidance sources note that extra calories are usually not needed during the first trimester. Symptoms, body size, and clinical circumstances still matter, so the estimate remains only a starting point.
3) Can I use pre-pregnancy weight instead of current weight?
You can, but current weight usually reflects present energy needs better. For consistent tracking, use the same weight approach each time and review trends with a qualified maternity clinician or dietitian.
4) Is this calculator suitable for twins?
It can provide a rough estimate for twins or higher-order pregnancies, but multiple pregnancy energy needs vary more widely. Use the result as a planning draft and confirm targets with your care team.
5) What activity level should I pick?
Choose the option that reflects your true average week, not your most active day. Overstating activity can raise the calorie estimate and lead to planning errors.
6) Why include a manual adjustment field?
Some pregnancies need individualized calorie targets because of body size, symptoms, glucose concerns, or clinician-led nutrition plans. The manual field lets you replace the default trimester addition when guidance already exists.
7) Does this calculator help with meal planning?
Yes. It divides the estimated daily calories by your chosen number of eating occasions, which helps you sketch meal and snack targets for the day.
8) Should I rely on this estimate alone?
No. Pregnancy nutrition should consider symptoms, lab results, appetite, fetal growth, and medical history. Use this calculator as a structured estimate, then personalize it with professional advice.