How many extra calories do I need during pregnancy?

In the first trimester, no extra calories are needed. Second trimester: ~340 extra cal/day. Third trimester: ~450 extra cal/day. These are estimates — your doctor may advise differently.

How much protein do I need while pregnant?

The recommended protein intake is about 71g per day during pregnancy, up from the standard 46g. Protein supports fetal growth, placental development, and increased blood volume.

What nutrients are most important in pregnancy?

Folate/folic acid (400–800mcg/day), iron (27mg/day), calcium (1000mg/day), DHA omega-3 (200–300mg/day), iodine (220mcg/day), and vitamin D (600 IU/day) are critical.

How much weight should I gain during pregnancy?

Recommendations depend on pre-pregnancy BMI. Underweight: 28–40 lbs. Normal: 25–35 lbs. Overweight: 15–25 lbs. Obese: 11–20 lbs.

How many extra calories in pregnancy?

In the first trimester, no extra calories are generally needed. In the second trimester, the common estimate is about 340 extra calories per day, and in the third trimester about 450 extra calories per day. These are added on top of your pre-pregnancy maintenance needs. Your actual needs vary with your pre-pregnancy weight, activity, and whether you are carrying twins — your prenatal provider gives the final guidance.

How much protein while pregnant?

The recommended dietary allowance for protein in pregnancy is about 71 grams per day, up from about 46 grams for non-pregnant women. Protein supports fetal growth, the placenta, and increased blood volume. Good sources include eggs, fish (low-mercury), poultry, dairy, legumes, and tofu. Spread it across meals, and talk to your provider about your individual target.

What foods to avoid in pregnancy?

Common foods to avoid or limit include raw or undercooked meat, fish, and eggs; raw fish and high-mercury fish (swordfish, king mackerel, tilefish, shark); unpasteurized dairy and juice; deli meats and hot dogs unless reheated to steaming; raw sprouts; and alcohol. Limit caffeine to under 200 mg per day (about one 12 oz coffee). This is a general list — check with your provider for a full guide.

Which trimester needs more calories?

The second and third trimesters. The first trimester usually needs no extra calories, even though nutrient quality matters from the start. The second trimester adds about 340 calories per day and the third about 450 calories per day on top of your pre-pregnancy maintenance level. This is why the calculator asks for your trimester.

Can I diet while pregnant?

Pregnancy is not the time for a calorie-restricted diet or weight-loss plan. Restricting calories can limit the nutrients your baby needs and is linked to lower birth weight. If you entered pregnancy at a higher weight, your provider may guide modest, careful changes, but this should always be supervised. Focus on food quality and the right total calories, not restriction.

Key vitamins in pregnancy?

The key nutrients are folate or folic acid (about 400 to 800 mcg per day, especially before and in early pregnancy, to protect the neural tube), iron (about 27 mg per day for blood production), calcium (about 1,000 mg per day for bones), DHA omega-3 (about 200 to 300 mg per day for brain and eye development), iodine (about 220 mcg per day), and vitamin D (about 600 IU per day). Most pregnant women take a prenatal vitamin to cover these.

How much weight should I gain?

Guidelines from the Institute of Medicine depend on your pre-pregnancy BMI: underweight (BMI below 18.5) about 28 to 40 lb; normal weight (18.5 to 24.9) about 25 to 35 lb; overweight (25 to 29.9) about 15 to 25 lb; obese (30 and above) about 11 to 20 lb. For twins, the ranges are higher. Your provider tracks your gain at each visit and adjusts as needed.

Most guidelines consider up to 200 mg of caffeine per day safe in pregnancy, which is about one 12 oz cup of brewed coffee. Higher intakes have been linked to miscarriage and lower birth weight in some studies, so many providers recommend limiting or cutting caffeine. Tea, chocolate, some sodas, and energy drinks also contain caffeine. Check with your provider for your situation.

🤰 FREE PREGNANCY NUTRITION CALCULATOR

Pregnancy Nutrition Calculator

Get your personalized calorie needs, protein targets, and essential nutrient recommendations for each trimester.

Enter Your Details

Current Weight (kg)

Height (cm)

Trimester

Activity Level

Frequently Asked Questions

Related Calculators

This is not medical advice — talk to your doctor. The sections below are educational estimates only. This calculator does not diagnose pregnancy, does not set a pregnancy weight-gain target, and does not recommend or change any prenatal vitamin, supplement, or medication. Always follow the guidance of your obstetrician or midwife for nutrition, weight gain, and supplements during pregnancy.

Nutrition by Trimester: Calorie & Protein Additions

Calorie needs rise as pregnancy progresses, but the first trimester usually needs no extra calories. Protein stays at about 71 g per day throughout:

Trimester	Extra Calories/day	Protein/day
1st (weeks 1 to 12)	0 (focus on quality)	71 g
2nd (weeks 13 to 26)	about 340	71 g
3rd (weeks 27 to 40)	about 450	71 g

Extra calories are added on top of your pre-pregnancy maintenance needs. Multiples (twins or more) have higher targets — your provider sets those.

Key Nutrients: Folate, Iron, Calcium, DHA

Beyond calories and protein, several nutrients are especially important in pregnancy. A prenatal vitamin helps cover them:

Nutrient	Daily Target	Why It Matters
Folate / folic acid	400 to 800 mcg	Neural tube protection in early pregnancy
Iron	27 mg	Supports increased blood volume
Calcium	1,000 mg	Bones and teeth development
DHA (omega-3)	200 to 300 mg	Fetal brain and eye development
Iodine	220 mcg	Thyroid function and brain development
Vitamin D	600 IU	Bone health and immune support

Folate is most critical before conception and in the first weeks, which is why it is recommended before you even try to conceive. Do not start high-dose individual supplements without your provider.

Foods to Avoid in Pregnancy

These foods carry a higher risk of foodborne illness (Listeria, Salmonella, Toxoplasma) or mercury exposure, which can affect a developing baby:

Raw or undercooked meat, poultry, fish, and eggs
Raw fish and sushi made with raw fish
High-mercury fish: swordfish, king mackerel, tilefish, shark
Unpasteurized milk, cheese, and juice
Raw or undercooked sprouts (alfalfa, clover, radish)
Deli meats and hot dogs, unless reheated to steaming

Alcohol (no safe amount is known)
High-dose vitamin A (retinol) supplements
Unwashed produce (toxoplasma risk)
Raw cookie dough or cake batter with raw eggs
Limit caffeine to under 200 mg per day
Avoid herbal supplements unless your provider approves

This is a general list, not exhaustive. Your prenatal provider can give you a full, up-to-date food safety guide.

How the Calculator Adjusts

The tool estimates your pre-pregnancy maintenance calories, then adds the trimester extra:

Formula (educational)

BMR = 655.1 + 9.563 x weight(kg) + 1.850 x height(cm) - 4.676 x age

TDEE = BMR x activity multiplier

Total calories = TDEE + trimester extra (0, 340, or 450)

Protein = 71 g; Iron = 27 mg; Folate = 400 mcg (T1) or 600 mcg (T2/T3); Calcium = 1,000 mg

The calculator uses the Harris-Benedict equation for women and standard pregnancy additions. It uses a fixed age estimate and does not adjust for pre-pregnancy BMI, multiples, or medical conditions — your provider does that.

Hydration in Pregnancy

Blood volume rises by about 40 percent during pregnancy, and amniotic fluid and breast tissue need water too. The Institute of Medicine recommends about 10 cups (2.3 liters) of total water per day from beverages for pregnant women, with more in hot weather or with activity.

Sip water through the day rather than drinking large amounts at once.
Listen to thirst; pale yellow urine is a good sign of hydration.
Limit sugary drinks and caffeine; choose water, milk, and herbal teas your provider approves.
If you have morning sickness, small sips or ice chips can help you keep fluids down.

See the Water Intake Calculator for a general target, then confirm with your provider.

Pregnancy Weight-Gain Ranges (IOM)

Recommended total weight gain depends on your pre-pregnancy BMI (Institute of Medicine guidelines, single baby):

Pre-Pregnancy BMI	Total Gain (lb)	Total Gain (kg)
Underweight (below 18.5)	28 to 40	12.5 to 18
Normal (18.5 to 24.9)	25 to 35	11.5 to 16
Overweight (25 to 29.9)	15 to 25	7 to 11.5
Obese (30 and above)	11 to 20	5 to 9

For twins, the ranges are higher (about 37 to 54 lb for normal BMI). Your provider tracks your gain at each visit and adjusts as needed.

Worked Example

A woman in her second trimester, 68 kg and 165 cm, lightly active:

Calculation

BMR = 655.1 + 9.563 x 68 + 1.850 x 165 - 4.676 x 25 = about 1,494 cal

TDEE = 1,494 x 1.375 = about 2,054 cal

Total = 2,054 + 340 = about 2,394 cal/day

Protein = 71 g; Iron = 27 mg; Folate = 600 mcg; Calcium = 1,000 mg

Result: about 2,394 cal/day with the 2nd-trimester addition

This is a starting estimate. Her provider may adjust it based on her pre-pregnancy BMI, activity, rate of weight gain, and how the baby is growing.

How to Use This Calculator & What to Do With Your Result

How to use it:

Enter your current weight (kg) and height (cm).
Select your trimester and activity level.
Click calculate to see your estimated daily calories, protein, iron, folate, and calcium.

What to do with your result:

Use the calorie estimate as a starting point, not a target to hit exactly every day.
Prioritize food quality: protein, vegetables, whole grains, and the key nutrients above.
Take a prenatal vitamin as your provider recommends to cover folate, iron, and iodine.
Follow the foods-to-avoid list and limit caffeine to under 200 mg per day.
Explore the Protein Calculator and Water Intake Calculator for related targets.
Bring your result to your next prenatal visit and confirm your plan with your provider.

Limitations of This Calculator

It estimates calorie needs from a formula and standard trimester additions, not from direct measurement.
It uses a fixed age estimate and does not adjust for pre-pregnancy BMI, body composition, or multiples.
Nutrient targets are general RDA values and do not reflect your personal medical or obstetric history.
It does not account for conditions like gestational diabetes, hypertension, or a restricted diet.
It does not diagnose pregnancy, set a personal weight-gain target, or recommend or change any prenatal vitamin or supplement.
Results are a starting point to discuss with your obstetrician or midwife, not a prescription.

Talk to Your Obstetrician or Midwife

Pregnancy nutrition is personal and changes with each visit. Talk to your prenatal provider if any of these apply:

You are unsure how much weight to gain or your gain is faster or slower than expected.
You have nausea or vomiting that limits what you can eat or drink.
You have a condition such as gestational diabetes, hypertension, or anemia.
You follow a restricted diet (vegan, vegetarian, food allergies) and want help meeting nutrient needs.
You are carrying twins or higher-order multiples.
You are deciding on a prenatal vitamin, iron dose, or any supplement.

Disclaimer: This pregnancy nutrition calculator provides educational estimates of calorie and nutrient needs from a formula and standard trimester additions. It does not diagnose pregnancy, set a personal weight-gain target, or recommend or change any prenatal vitamin, iron dose, supplement, or medication. Nutrition needs in pregnancy vary and should be set by your obstetrician or midwife. This is not medical advice — talk to your doctor.