How much sugar can I have per day?

It depends on which guideline you follow. The WHO recommends keeping free sugars below 10% of your total daily energy intake — roughly 50 g (12 tsp) for a 2,000 kcal diet — and ideally below 5% (25 g / 6 tsp). The American Heart Association is stricter: 25 g (6 tsp) for women and children, 36 g (9 tsp) for men. The NHS recommends no more than 30 g of free sugars per day for adults, with lower limits for children.

What are free sugars or added sugars?

Free sugars are all monosaccharides and disaccharides added to foods by the manufacturer, cook or consumer, plus sugars naturally present in honey, syrups, fruit juices and fruit juice concentrates. They do NOT include sugars locked inside intact fruit, vegetables or milk. Added sugars (the term used by the AHA and on US nutrition labels) are essentially the same concept, minus naturally occurring honey and fruit juice sugars, though in practice the two groups are nearly identical for the purposes of daily limits.

How is my personalised limit calculated?

The tool estimates your basal metabolic rate using the Mifflin-St Jeor equation (10 × weight_kg + 6.25 × height_cm − 5 × age + 5 for men; same minus 161 for women), then multiplies by 1.55 to account for light-to-moderate activity. Your WHO limit is then 10% (or 5%) of that figure divided by 4 kcal per gram of sugar. You can override the calorie estimate by typing your own figure.

How many teaspoons is a gram of sugar?

One level teaspoon of granulated sugar weighs approximately 4.2 grams. So 25 g equals about 6 teaspoons and 50 g equals about 12 teaspoons. The calculator shows both units side by side so you can visualise your intake.

Does fruit count towards my sugar limit?

Whole fruit does not count. The sugars inside intact fruit cells are not classified as free or added sugars by any major health body, because the fibre matrix slows absorption significantly. However, fruit juice (even fresh-squeezed with no added sugar) does count, because juicing breaks the cells and releases the sugars in a form the body treats similarly to added sugar.

Why does the AHA limit differ by sex?

The AHA set its recommended limits based on observed dietary patterns and cardiovascular outcomes in population studies, which showed men typically consuming more total calories. The fixed-gram limits (36 g for men, 25 g for women) represent roughly 9% and 6% of average energy intakes respectively. The WHO percentage-based approach (10% of YOUR calories) automatically adjusts for individual energy needs, which is why the two systems give different numbers for different people.

Sugar Intake Calculator

Eating too much sugar is one of the most reliably modifiable dietary risk factors for obesity, type 2 diabetes, dental caries and cardiovascular disease. Yet most people genuinely do not know how many grams of sugar they are consuming each day — in part because sugar hides in bread, pasta sauces, flavoured yoghurts and sports drinks, not just in confectionery. This calculator makes the invisible visible: log what you eat, see the grams and teaspoons stack up in real time, and compare your running total against the limits published by the World Health Organization (WHO), the American Heart Association (AHA) and the UK’s National Health Service (NHS).

How it works

The tool is entirely client-side — nothing you type ever leaves your browser.

Step 1 — Profile. Enter your age, sex, weight and height. The calculator uses the Mifflin-St Jeor equation to estimate your resting metabolic rate (BMR) and then multiplies by 1.55 to approximate a lightly active total daily energy expenditure. If you know your actual calorie intake from an app or dietitian assessment, you can override the estimate.

Step 2 — Choose a guideline. Toggle between WHO (10% of daily energy), AHA (fixed grams by sex and age) or NHS (fixed grams by age). The limit displayed in the gauge updates immediately.

Step 3 — Log food. Pick from 20 preset items (including cola, energy drinks, chocolate, doughnuts, ketchup, flavoured yoghurt, cereals and more) with serving quantities, or type any custom item and its sugar content in grams. Each item shows its sugar in grams and the calories it contributes (at 4 kcal/g).

Step 4 — Read the gauge. A colour-coded bar fills from green through amber to red as you approach and exceed your chosen limit. A comparison table shows your status against all four thresholds simultaneously.

Formulas used

WHO percentage limit: WHO_limit (g) = (daily_kcal × 0.10) ÷ 4 kcal/g. The 5% ideal limit halves this figure.

Mifflin-St Jeor BMR:

Men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161

Sugar energy: 1 g sugar = 4 kcal (same as all carbohydrates).

Teaspoon conversion: 1 level teaspoon granulated sugar ≈ 4.2 g, so tsp = grams ÷ 4.2.

Worked example

A 35-year-old woman, 65 kg, 165 cm, lightly active:

BMR = 10 × 65 + 6.25 × 165 − 5 × 35 − 161 = 650 + 1031 − 175 − 161 = 1,345 kcal
Estimated TDEE = 1,345 × 1.55 = 2,085 kcal/day
WHO 10% limit = (2,085 × 0.10) ÷ 4 = 52 g (12.4 tsp)
WHO 5% ideal = 26 g (6.2 tsp)
AHA limit for a woman = 25 g (6 tsp)
NHS limit for an adult = 30 g (7.1 tsp)

A typical “healthy” day might include a flavoured yoghurt (12 g), a glass of orange juice (18 g) and one biscuit (7 g) — that is already 37 g, over the AHA and NHS limits and 71% of the WHO 10% limit, before a single chocolate bar or soft drink.

Item	Sugar
Can of cola (330 ml)	35 g
Chocolate bar (~45 g)	24 g
Flavoured yoghurt (125 g)	12 g
Tablespoon of ketchup	4 g
Bowl of sweetened cereal	9 g

Every figure is computed in your browser. No food log or personal data is uploaded anywhere.