Boiled sweet corn is a moderate-calorie starch that supplies about 77 to 90 calories per medium ear on the cob (around 90 grams after the husk is removed), roughly 143 calories per cup of kernels (164 grams), and close to 96 calories per 100-gram serving. The exact figure shifts with cob size, variety, cook time, and whether the kernels were weighed before or after they absorbed water in the pot.
This guide breaks down boiled corn’s calorie count across serving sizes, compares it to rice and quinoa, and explains how cooking affects its nutrition for anyone tracking macros.
Calorie Counts by Serving Size, From One Cob to a Full Cup
Serving size is where most corn-tracking goes wrong. A “cob” can weigh anywhere from 60 to 140 grams depending on variety, and a “cup” of kernels can hold a surprisingly different volume depending on how tightly you pack it. The table below puts every common unit on one page so you can pick the one that matches your actual portion.
| Serving Size | Weight | Approximate Calories |
|---|---|---|
| 1 ounce (USDA label unit) | 28 g | ~27 |
| 100 grams | 100 g | ~96 |
| Half-cup of kernels | 82 g | ~72 |
| One cup of kernels | 164 g | ~143 |
| Baby ear | 60 g | ~50–60 |
| Medium cob | 90 g | ~77–90 |
| Large cob | 118 g | ~110–125 |
| One pound of kernels | 454 g | ~435 |
The medium cob is the most useful number for everyday eating because it matches what most people actually sit down to. The cup and 100-gram figures are the ones your tracking app is almost certainly pulling from, so they matter most when precision counts. A one-pound batch is mostly relevant for meal prep or feeding a crowd.
One detail that catches people off guard: boiled corn weighs more than raw corn. Water absorption during cooking adds roughly 20–30% mass, so the same ear that started at 75 grams raw can hit 90 grams once it comes out of the pot. The calorie content stays the same because the cob absorbed water, not fat, but the gram-based number shifts under your hands.
If you don’t own a kitchen scale, the cup-of-kernels measurement is your safest default. A level cup of cut kernels is the standard serving most recipe databases and tracking apps use, and it’s easier to eyeball than a “medium cob” that might be hiding a 30-gram swing.
Standardizing on the cup also sets up a fair comparison with the macros and micros you’re about to weigh in.
Macronutrients and Micronutrients Behind the Calorie Number
Calories tell you how much energy a food delivers, but they don’t tell you what kind of energy it is. Boiled corn leans heavily on carbohydrates, with a small but meaningful amount of protein and very little fat. Understanding the split helps you decide when corn earns a place on your plate and when it should swap out for something else.
Carbohydrates Dominate the Calorie Profile
Carbs supply about 80% of the total calories in boiled corn. A 100-gram serving contains roughly 21 grams of carbohydrate, including 2.7 grams of dietary fiber and about 5 grams of natural sugars. The fiber is mostly insoluble, which supports healthy digestion but doesn’t do much on its own to slow the rise in blood sugar after a meal.
Net carbs land around 18–19 grams per 100 grams, which is the figure that matters if you’re tracking for a low-carb or diabetic-friendly plan. That number puts corn in the same conversation as rice and potatoes, well above leafy greens or cruciferous vegetables.
Protein and Fat Sit on the Low End
Boiled corn delivers about 3.4 grams of protein and 1.8 grams of fat per 100-gram serving. Neither number is impressive on its own, but the protein is higher than most grains manage and includes some lysine, an amino acid that rice and wheat tend to lack. Fat content is low enough that the food needs almost no adjustment on a low-fat eating plan.
The micronutrient side is where corn quietly earns points. A 100-gram serving of boiled yellow corn delivers meaningful amounts of thiamine (vitamin B1), folate, vitamin B6, vitamin C, magnesium, and potassium. It also contains lutein and zeaxanthin, two carotenoid antioxidants that concentrate in the retina and are linked to long-term eye health, the same compounds that give corn its yellow color.
Boiling gets a bad rap for leaching nutrients, but the losses are smaller than people assume. Vitamin C and some B vitamins do seep into the cooking water, yet the cob itself retains enough to make a real nutritional contribution, especially when the cooking time stays under 10 minutes.
How Boiling Changes Corn’s Calories, Weight, and Nutrients
The cooking method matters less for calories than for texture and flavor, but a few specific details are worth knowing. Boiling is the lowest-calorie way to prepare corn because nothing gets added beyond water, and that one choice keeps the gram-for-gram number honest.
Water Absorption Versus Added Fat
Boiling adds water to each kernel, which can increase the cob’s weight by 20–30% without changing its energy content. The same ear that was 75 grams raw is closer to 90 grams after a five-minute boil, but a calorie is still a calorie regardless of how much water is riding along. By contrast, roasting, grilling, or microwaving an ear with oil or butter can double or triple the total calories before you take your first bite.
Water-soluble nutrients like vitamin C and several B vitamins do leach into the pot, typically losing 10–25% of their original content. If you’re optimizing for nutrient density, steaming or microwaving the cob preserves slightly more of those vitamins, though the difference is modest in a real-world diet.
What Toppings Actually Do to the Calorie Total
A plain boiled cob stays near 90 calories. The toppings are where the number moves.
One tablespoon of butter adds about 100 calories, one tablespoon of olive oil adds about 120, and a heavy pinch of salt adds essentially nothing. Salt brings flavor without energy, while fat is the only topping that meaningfully changes the meal’s total.
A “loaded” ear with two tablespoons of butter, a sprinkle of cheese, and a drizzle of mayo can climb past 300 calories, more than three times the plain version. If you track corn for weight management, log the toppings separately and treat the cob itself as your baseline.
With that cooking math settled, it helps to see where a boiled cob lands against the starches people swap it for.
Boiled Corn Next to Rice, Quinoa, and Potato
Side-by-side comparisons are where corn’s reputation gets complicated. It looks like a vegetable on the plate but behaves like a starch next to rice or a baked potato, which is exactly why a calorie comparison table is more useful than a “corn is healthy” recap.
| Food (cooked, plain) | Per 100 g | Per Standard Serving | Standard Serving |
|---|---|---|---|
| Boiled yellow corn kernels | ~96 cal | ~143 cal | 1 cup (164 g) |
| White rice, cooked | ~130 cal | ~205 cal | 1 cup (158 g) |
| Brown rice, cooked | ~111 cal | ~216 cal | 1 cup (195 g) |
| Quinoa, cooked | ~120 cal | ~222 cal | 1 cup (185 g) |
| Boiled potato (cubed) | ~87 cal | ~134 cal | 1 cup (156 g) |
| Baked potato, medium | ~93 cal | ~161 cal | 1 medium (173 g) |
On a per-100-gram basis, boiled corn is the lowest-calorie option of the bunch by a small margin, edging out boiled potatoes and undercutting both white and brown rice. Quinoa lands in the middle of the pack, slightly higher in calories than corn but noticeably higher in protein, which is why it often gets promoted as the “better” grain.
These numbers line up with the standard USDA FoodData Central entries for each cooked food, measured without added fat or salt.
Glycemic Index and Blood Sugar Impact
Sweet corn scores a glycemic index of roughly 52–60, depending on the variety and how long it was cooked. That puts it in the medium range, comparable to brown rice and noticeably lower than a baked potato, which often lands above 70. For anyone managing blood sugar, the difference between corn and potato on a glucose monitor is real and worth noticing.
Pairing corn with a lean protein and a non-starchy vegetable slows glucose absorption further, which matters more than the raw glycemic number when the food is part of a mixed meal.
Boiled Corn on a Weight-Loss or Calorie-Deficit Plan
Boiled corn is a starch that can absolutely fit a deficit, but it earns that spot by portion, not by category. A plain medium cob at roughly 85 calories is one of the lowest-calorie starch options available, yet the moment butter or mayo lands on top, the math changes fast.
A Practical Daily and Per-Meal Cap
For most adults in a moderate deficit, one to two cobs per meal (or one full cup of kernels) is a reasonable upper limit. That range keeps the corn serving in the 85–180 calorie band, leaving plenty of room for protein, non-starchy vegetables, and a small amount of healthy fat.
Tracking accuracy is where most corn logs go sideways. A “medium cob” can hide a 30-calorie swing if the cob is oversized, and a “cup of kernels” can drift if the kernels are packed tight. Weighing in grams or going by the 100-gram reference removes the guesswork, and it lines up with how USDA FoodData Central reports the food.
Corn for Diabetics and Low-Carb Eaters
With roughly 19 grams of net carbs per 100-gram serving, corn reads as a grain on a glucose monitor even when it’s served like a vegetable. For a diabetic-friendly or low-carb plan, the carb load is the real constraint, and a small portion (half a cob, around 45 calories and 9 net carbs) is the safer ceiling.
Always pair it with protein, fat, or fiber from non-starchy vegetables to blunt the glucose response, and check your own readings to see how your body actually responds. Individual responses to corn vary more than the textbook numbers suggest.
Those caveats about individual response are exactly the kind of nuance worth carrying into the final take.
Bottom Line
Boiled corn is a moderate-calorie, starch-leaning side that behaves more like rice than broccoli. A plain ear sits near 90 calories, but the toppings that usually travel with it can push a single serving past 200 without much effort.
Use 100 grams or one cup of kernels as the default logging unit, treat a medium cob as roughly 85 calories, and stop counting corn as a free vegetable if macros actually matter for your goal. The calorie number is honest. The category it gets filed under often isn’t.
FAQ
How many calories are in one boiled ear of corn?
Pulling the husk off a medium ear of boiled sweet corn reveals about 90 grams of bright kernels that deliver roughly 77 to 90 calories. The range depends on variety, field size, and cook time, with larger ears at 118 grams running closer to 110 to 125 calories.
How many calories are in one cup of boiled corn kernels?
A heaping measuring cup of boiled corn kernels tips the scale at around 164 grams and packs in approximately 143 calories. This is the standard serving most recipe databases and calorie-tracking apps pull from, so it tends to be the cleanest number to log at dinner.
How many calories in 100g of boiled sweet corn?
A 100-gram serving of boiled yellow sweet corn comes in at about 96 calories, backed by 21 grams of carbohydrate and around 2 grams of fat.7 grams of fiber, and 3.4 grams of protein. The 100-gram figure is the easiest unit to scale up or down when you’re logging a mixed meal.
Does boiling corn add or remove calories compared to raw corn?
Boiling doesn’t add or remove calories, but it does add water. A raw ear at 75 grams can weigh 90 grams after a five-minute boil, which makes the cooked cob look heavier on a scale even though the energy content is unchanged. Toppings are the only thing that actually moves the calorie number.
Is boiled corn good for weight loss?
A modest ear of boiled corn can slot neatly into a calorie-controlled eating plan, especially when butter and salt stay on the side. A plain medium cob at about 85 calories is one of the lower-calorie starches available, and pairing it with a lean protein and a non-starchy vegetable slows the glucose response enough to keep you full.
Can we eat boiled corn during weight loss?
Yes, in modest portions. A plain medium cob at roughly 85 calories fits comfortably into most calorie-deficit budgets, especially when paired with a lean protein and a non-starchy vegetable to slow glucose absorption. The toppings, not the corn, are what usually push a serving over budget.
