Calculator
Use the three-column responsive form below. Large screens show three columns, medium screens show two, and mobile shows one.
Example Data Table
These sample values show how the calculator can be used for planning comparisons.
| Case | Age | Weight | Height | Week | Formula | Baseline BMR | Adjusted BMR | Daily Energy |
|---|---|---|---|---|---|---|---|---|
| Example A | 28 | 62 kg | 164 cm | 10 | Mifflin-St Jeor | 1334 kcal | 1334 kcal | 1834 kcal |
| Example B | 31 | 70 kg | 167 cm | 24 | Mifflin-St Jeor | 1413 kcal | 1753 kcal | 2410 kcal |
| Example C | 35 | 82 kg | 170 cm | 33 | Harris-Benedict | 1529 kcal | 1981 kcal | 3071 kcal |
Formula Used
Mifflin-St Jeor for women:
BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years) − 161
Harris-Benedict Revised for women:
BMR = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) − (4.330 × age in years)
Pregnancy adjustment used here:
Trimester 1: +0 kcal/day
Trimester 2: +340 kcal/day
Trimester 3: +452 kcal/day
Adjusted Pregnancy BMR = Selected BMR + Trimester Addition + Custom Adjustment
Estimated Daily Energy = Adjusted Pregnancy BMR × Activity Factor
How to Use This Calculator
- Choose metric or imperial units.
- Select the BMR equation you want to use.
- Enter age, body weight, and height.
- Add gestational week to auto-detect trimester, or pick trimester manually.
- Select your activity level for a daily energy estimate.
- Add a custom adjustment only when you need a personalized planning offset.
- Press the calculate button.
- Review the result summary, chart, and export options above the form.
FAQs
1. What does this calculator estimate?
It estimates resting calorie needs during pregnancy, then applies activity and trimester adjustments. It is meant for general planning, not medical treatment decisions.
2. Why are there two BMR formulas?
Different equations can produce slightly different estimates. Offering both helps you compare common methods and choose the one you prefer for consistent tracking.
3. Why does gestational week matter?
Gestational week helps the tool assign a trimester automatically. That trimester then changes the pregnancy calorie addition used in the estimate.
4. Is the result the same as a meal plan?
No. This tool estimates energy needs only. A meal plan also considers protein, symptoms, nutrient quality, appetite, and any clinical guidance.
5. Should I use current weight or pre-pregnancy weight?
Most users enter current weight for a current estimate. For a longer-term nutrition strategy, compare results with your clinician or dietitian.
6. What is the custom adjustment field for?
It lets you add or subtract calories for personalized planning. Use it carefully and preferably only when guided by a qualified professional.
7. Can I use this every week?
Yes. Rechecking weekly can help you monitor changing estimates as pregnancy progresses, body weight changes, or activity shifts.
8. Does this replace medical advice?
No. Pregnancy energy needs vary by symptoms, fetal growth, activity, and health history. Always use professional guidance for medical decisions.