Pregnancy Calorie Calculator
See a rough estimate of how many calories you may need during each trimester and while breastfeeding, added on top of your pre-pregnancy maintenance calories.
Please read: Pregnancy nutrition should be guided by your doctor or midwife. This tool gives population-average estimates only and is not a substitute for prenatal care. Do not restrict calories to lose weight during pregnancy unless your clinician specifically advises it.
Your details
Enter your pre-pregnancy weight and usual activity.
The first trimester adds no extra calories for most people. Additions are population averages, your clinician may advise different amounts, especially with twins, a high or low starting BMI, or gestational diabetes.
Maintenance plus your stage
You do not eat for two. Extra calorie needs during pregnancy are far smaller than most people expect: roughly nothing in the first trimester, then about 340 extra calories a day in the second trimester and 450 in the third, according to Institute of Medicine guidance. This calculator estimates your pre-pregnancy maintenance level and layers the appropriate addition on top. The quality of those calories, protein, iron, folate, calcium, and omega-3s, matters as much as the quantity.
How many extra calories each trimester really needs
In the first trimester most people need no additional calories at all, even though nausea and fatigue are common. The baby is still tiny and the energy cost is minimal. Forcing extra food this early tends to add fat rather than support the pregnancy.
The second trimester adds about 340 calories a day, and the third about 450, to support the baby's growth and your increased blood volume and tissue. That is roughly a substantial snack and a small meal, not a second dinner. A glass of milk, a handful of nuts, and a piece of fruit can cover much of it.
Healthy weight gain, not calorie counting
Clinicians track pregnancy nutrition mainly through weight gain, not calorie totals. Recommended total gain depends on your starting BMI: roughly 25 to 35 pounds if you began at a healthy weight, more if underweight and less if overweight. Your provider will chart your gain and adjust guidance if you are above or below the curve.
Because of this, treat the number here as background context rather than a target to hit precisely. Eating to appetite with nutritious foods, while your provider monitors your gain, is the standard approach.
Breastfeeding often needs more than pregnancy
Exclusive breastfeeding burns roughly 450 to 500 calories a day to produce milk. Guidance commonly suggests eating about 330 extra calories a day and drawing the remainder from fat stores gained during pregnancy, which is part of how nursing supports gradual postpartum weight loss. Stay well hydrated and keep protein and calcium high.
If you are exclusively pumping or feeding twins, needs are higher. As always, your clinician or a lactation consultant can personalize this.
Frequently Asked Questions
Roughly none in the first trimester, about 340 more per day in the second, and about 450 more in the third, per Institute of Medicine guidance. This calculator adds those amounts to your estimated pre-pregnancy maintenance calories.
Usually not. Energy needs barely change in the first trimester, so most people maintain their pre-pregnancy intake even though appetite and nausea fluctuate. Focus on folate, fluids, and tolerable nutritious foods rather than extra calories.
No, not unless your clinician specifically advises it. Deliberately restricting calories during pregnancy can deprive the baby of nutrients. Weight management is handled through your provider's guidance on healthy total weight gain, not calorie cutting.
Milk production costs about 450 to 500 calories a day. Common guidance is to eat roughly 330 extra calories daily and let the rest come from fat stored during pregnancy. Needs are higher for exclusive pumping or feeding multiples.
It depends on your starting BMI. General guidance is about 25 to 35 pounds for a healthy pre-pregnancy weight, roughly 28 to 40 if underweight, and 15 to 25 if overweight. Your provider tracks this and personalizes it.
Treat it as educational context only. Pregnancy nutrition is highly individual and should be guided by your doctor or midwife, who accounts for your health history, BMI, and any conditions such as gestational diabetes.
Important: This pregnancy calorie estimate is for general education only and is not medical advice or a substitute for prenatal care. Calorie needs in pregnancy and lactation vary widely. Always follow the guidance of your doctor, midwife, or registered dietitian, and never restrict calories to lose weight while pregnant unless specifically instructed by your clinician.