Food Calories by Weight Calculator
Calories in a portion from calories per 100 g and the grams you eat.
Your result
Use the calories per 100 g on the packet or a food database. Weighing a portion is more accurate than estimating by eye.
Medical disclaimer: This tool is for education and is not medical advice. Read more.
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Frequently asked questions
What does the Food Calories by Weight Calculator do?
Calories in a portion from calories per 100 g and the grams you eat. Enter your values and the result and chart update instantly.
How accurate is it?
It uses published, widely used formulas. Results are estimates for education and planning, not a diagnosis. Talk to a qualified clinician about decisions affecting your health.
Is my information stored or shared?
No. All calculations run in your browser and nothing you type is sent to a server or saved.
What can I search to find this tool?
People find it by searching for: calories in 150 grams; calories per gram of food; portion calorie calculator.