How Many Calories Is in Cucumber

Cucumbers are one of the lowest-calorie foods you can eat. A whole cucumber (around 300 grams) has only 45 calories, while a half cucumber contains about 20–23 calories. A one-cup serving of sliced cucumber (with skin) delivers just 15–16 calories, making it an ideal snack or salad base for calorie-conscious diets. Because cucumbers are over 95% water, they fill you up without adding significant energy intake.

Calories in Cucumber by Form and Serving Size

The calorie content of cucumber stays low across forms. Whether it’s sliced, diced, spiralized, or whole, cucumbers contribute very little to your total intake. Peeled cucumbers are slightly lower in calories, but removing the skin also removes some fibre and nutrients. Pickled cucumbers (like gherkins or dill pickles) remain low in calories — typically 5 to 10 calories per spear — but often include added sodium, vinegar, and sometimes sugar, which change their nutritional profile.

Nutritional Breakdown of Cucumber

Cucumbers contain minimal calories from carbs, virtually no fat, and less than 1 gram of protein per cup. One cup of sliced cucumber offers around 4 grams of carbs, including less than 2 grams of natural sugar and about 0.5 grams of fibre. They’re rich in vitamin K, a source of antioxidants, and deliver small amounts of potassium and magnesium. While not packed with macronutrients, their hydration, volume, and crunch make them a powerful tool for appetite management.

Hydration and Appetite Control

Cucumbers act like edible water. They hydrate the body while offering a crunchy texture that satisfies cravings for snacks like crisps or crackers. Their high water content expands in the stomach and adds bulk to meals, helping you feel full with very few calories. This makes cucumbers a go-to food for volume eaters, intermittent fasters, or anyone trying to stretch meals without stretching their calorie budget.

Glycemic Impact and Blood Sugar Response

Cucumbers have a very low glycemic index, typically under 15, which means they have almost no effect on blood sugar. This makes them an excellent food for people managing diabetes, insulin sensitivity, or fat loss goals. Because they digest slowly and contain fibre and water, cucumbers support stable energy and appetite regulation when combined with protein or healthy fats.

How Cucumbers Fit Into a Weight-Loss Diet

Cucumbers are ideal for weight loss because they’re low-calorie, high-volume, and naturally refreshing. They can be used in salads, wraps, dips, or eaten on their own as a crunchy snack. Dipping cucumbers into hummus, salsa, or Greek yogurt keeps the calorie count low compared to chips or bread-based snacks. They also work well in detox waters and smoothies, adding flavour without spiking sugar or calories.

Cucumbers Are “Free Foods” on Most Diet Plans

Because cucumbers are so low in calories, most structured diets — from calorie counting to Weight Watchers and Slimming World — classify them as free foods. That means you don’t have to weigh, measure, or track them. You can eat cucumbers in large quantities without affecting your calorie budget. This makes them incredibly useful as a buffer food for snacking, craving control, or extending meals.

You Burn Almost as Many Calories Digesting Them

Cucumbers are one of the closest foods to what’s called “negative calorie” — meaning the energy required to chew, digest, and absorb them is nearly equal to what they provide. While the idea of true negative-calorie foods is mostly a myth, cucumbers come close. The thermic effect (calories burned in digestion) is minor, but because the intake is so low, the net gain is minimal — which is exactly what makes cucumbers powerful in a calorie deficit.

They’re a Cheat Code for Cravings

Crunch, texture, and volume play a massive role in satisfying hunger signals — especially in the evening. Sliced cucumber with lemon juice, vinegar, sea salt, or herbs can mimic the ritual of snacking without the calories of crisps, crackers, or sweets. This makes cucumber a smart substitute for emotional eating or "mouth boredom" — when you’re not truly hungry but still want something to chew.

Cucumber-Based Meals Extend Satiety

Adding cucumber to rice bowls, sandwiches, omelettes, wraps, or salads increases volume and satiety without significantly altering macros. When you need to make a small portion of protein or carbs feel like more food, cucumbers are a volume hack. They also bring a cold, crisp contrast to warm foods — which increases sensory satisfaction, another way to control portion sizes without mental restriction.

Cucumber Bloat Is Rare — Unlike Other Veggies

Unlike cauliflower, broccoli, or cabbage, cucumbers rarely cause gas or bloating — even when eaten raw. That makes them one of the safest veggies for people with IBS, sensitive digestion, or early-stage diet transitions. They’re also easy on the stomach during fasts, cuts, or detox-style plans where simplicity and low volume are key.

Freedom To Snack

Cucumbers don’t just offer nearly zero calories — they offer freedom. Freedom to snack. Freedom to fill your plate. Freedom to eat without counting. And freedom to stay in control when cravings strike. That’s what makes them elite for fat loss, habit-building, and sustainable dieting.

Cucumber Is the Ultimate “Filler Food”

Cucumbers are the poster child for what’s called low energy density eating. That means you can eat a large volume of cucumber for very few calories — which helps stretch meals, manage hunger, and keep portions visually satisfying without blowing your calorie budget. In practical terms, a 300g cucumber takes up more space in your stomach than two slices of pizza — and delivers less than 50 calories total. That visual and physical fullness is a huge win for anyone who struggles with portion control.

Great for Carb Control Without Giving Up Crunch

If someone is cutting carbs or managing blood sugar, cucumber is a way to keep texture and bite in meals without starch or sugar spikes. Swapping things like crackers, croutons, or breadsticks for cucumber slices in dips or side dishes can shave off hundreds of calories per week — and over time, that makes a real difference in fat loss or maintenance.

Underrated as a Hydration Tool

Dehydration often shows up as hunger or cravings — especially late in the day. Cucumbers are over 95% water, which makes them a passive hydration tool for people who don’t drink enough fluids. A few servings of cucumber can top up hydration levels, improve digestion, and reduce snacking that's really just thirst in disguise.

Safe for Late-Night Eating

One of the few foods that’s truly safe to eat before bed without affecting digestion, fat burning, or sleep quality is cucumber. It’s low in sugar, won’t spike insulin, and won’t overload your system. If you absolutely must snack at night, cucumbers are about the closest you’ll get to guilt-free volume. You could eat a whole one and still stay under 50 calories, with no bloat and no blood sugar crash.

Used in Cut Phases by Bodybuilders and Athletes

Cucumbers are heavily used in body recomposition diets because they offer mental satisfaction without energy cost. In physique prep, where calories are strict and hunger is constant, athletes rely on cucumbers to chew, fill space, and calm appetite without disrupting their tight macros. If it works on the most extreme diets in sport, it works for real-life weight loss, too.

Hydrating

Cucumbers aren’t just low-calorie — they’re strategically powerful. They support hydration, reduce overeating, control texture cravings, and help meals feel physically satisfying. Whether you’re cutting, maintaining, or just eating clean, cucumbers give you maximum room to eat, with minimum calorie cost. That’s rare — and incredibly valuable.

Summary

A full cucumber contains just 45 calories, while a cup of sliced cucumber has about 15–16. They’re mostly water, low in carbs, and offer fibre, vitamin K, and hydration. Because they’re filling without being fattening, cucumbers are one of the most efficient foods you can eat in a calorie deficit. Whether you’re managing weight, blood sugar, or hydration, cucumbers deliver high satiety with almost no calorie cost.