How does Kairo track calories?

Kairo uses advanced AI to analyze photos of your food and automatically calculate calories and macronutrients. Simply take a photo of your meal, and Kairo does the rest.

Is Kairo available on Android?

Currently, Kairo is exclusively available for iOS devices. We are working on an Android version for the future.

How much does Kairo cost?

Kairo offers a yearly subscription with a 3-day free trial, as well as a monthly subscription. You can test all features during the trial and cancel anytime before it ends.

Does Kairo work with Apple Health?

Yes, Kairo fully integrates with Apple Health to sync your nutrition data and provide a comprehensive health overview.

How many calories do I need per day?

Your daily calorie needs depend on factors like age, gender, weight, height, and activity level. Kairo automatically calculates your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) based on your profile using the scientifically recognized Mifflin-St Jeor equation.

What is the difference between BMR and TDEE?

BMR (Basal Metabolic Rate) is the number of calories your body burns at rest to maintain basic functions. TDEE (Total Daily Energy Expenditure) includes your BMR plus calories burned through physical activity and digestion. TDEE is the total number of calories you need per day.

What is the Body Map in Kairo?

The Body Map is a unique Kairo feature that shows you at a glance how your nutrition supports different body systems — brain, heart, muscles, bones, digestion, and skin & immune system. It provides personalized insights based on your daily food intake.

What makes Kairo different from other calorie trackers?

Kairo combines AI-powered food scanning with features like Body Map nutrition insights, social group tracking with emoji reactions, streak motivation systems, and beautiful iOS widgets. It focuses on simplicity and design while providing comprehensive nutrition tracking.

What is BMI and how is it calculated?

BMI (Body Mass Index) is calculated by dividing your weight in kilograms by your height in meters squared: BMI = weight / (height in m)². A BMI of 18.5-24.9 is considered normal weight. Note that BMI does not account for muscle mass or body composition.

How many calories are in Onion?

Onion has 40 kcal per 100 g. A typical 110 g serving contains about 44 kcal.

How much protein is in Onion?

Onion provides 1.1 g of protein per 100 g.

How many carbs are in Onion?

Onion contains 9.3 g of carbohydrates per 100 g, of which 4.2 g is sugar.

How much fat is in Onion?

Onion contains 0.1 g of fat per 100 g. It also provides 1.7 g of fiber per 100 g.

Is Onion good for weight loss?

With only 40 kcal per 100 g, Onion is low in calories and fits easily into a weight-loss diet.

All Foods

Vegetables

Onion

40 kcal per 100g

Serving Size

Nutrition Facts

Serving size: 100g

Calories40

per serving

Total Fat0.1g

Total Carbohydrate9.3g

Dietary Fiber1.7g

Total Sugars4.2g

Protein1.1g

Sodium4mg

Health Info

Onions are low in calories and a notable source of quercetin, an antioxidant flavonoid, plus prebiotic fibers that feed gut bacteria. Their sulfur compounds — released when chopped — are being studied for cardiovascular benefits.

Macros per 100g

40kcal

Calories

1.1g

Protein

9.3g

Carbs

0.1g

Fat

Track Onion in Kairo

Scan your food with AI and automatically track calories and macros. No manual entry needed.

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Frequently Asked Questions

How many calories are in Onion?: Onion has 40 kcal per 100 g. A typical 110 g serving contains about 44 kcal.
How much protein is in Onion?: Onion provides 1.1 g of protein per 100 g.
How many carbs are in Onion?: Onion contains 9.3 g of carbohydrates per 100 g, of which 4.2 g is sugar.
How much fat is in Onion?: Onion contains 0.1 g of fat per 100 g. It also provides 1.7 g of fiber per 100 g.
Is Onion good for weight loss?: With only 40 kcal per 100 g, Onion is low in calories and fits easily into a weight-loss diet.

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