Caffeine Calculator

This caffeine calculator adds up how much caffeine you get through the day from the drinks you have, then shows how your total compares with the 400 mg a day that health authorities regard as moderate for most healthy adults. You enter how many cups of coffee and tea you drink, plus any energy drinks and colas, and the calculator multiplies each by its average caffeine content and totals them up. It then works out that total as a percentage of the 400 mg guideline, how much headroom you have left for the day, and roughly how many cups of coffee your intake adds up to. Caffeine is the most widely used stimulant in the world, and a moderate amount helps most people feel alert, but going well over your usual level can leave you jittery, anxious and unable to sleep. Seeing your day totalled in one number makes it easy to spot when an extra energy drink or a late long black would tip you over. The caffeine figures are averages, since the real amount depends on the brand, the cup size and how strong you make it, so treat the total as a useful estimate. The 400 mg marker is a general adult guideline: pregnancy is lower at about 200 mg, and children and sensitive people need much less. This tool is general information, not medical advice.

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366 mg
estimated caffeine today
Of 400 mg guideline92%
Remaining today34 mg
Coffee-cup equivalent3.9

366 mg is within the 400 mg general adult daily guideline, with 34 mg to spare.

Averages: coffee 95 mg, tea 47 mg, energy drink 80 mg, cola 34 mg. Actual amounts vary by brand and size. The 400 mg guideline is for healthy adults; pregnancy is about 200 mg. General information, not medical advice.

How it works

The calculator multiplies the number of each drink by its average caffeine content, 95 mg for a cup of coffee, 47 mg for tea, 80 mg for an energy drink and 34 mg for a cola, and adds them into a daily total in milligrams. It compares that total with the 400 mg a day that health authorities such as FSANZ treat as moderate for healthy adults, showing the total as a percentage of the guideline and the milligrams you have left. The coffee-cup equivalent is your total divided by 95, so you can picture it in cups.

Worked example

Say you have 3 cups of coffee, 1 cup of tea and 1 cola. The coffee gives 3 times 95, or 285 mg, the tea adds 47 mg, and the cola adds 34 mg, for a total of 366 mg. That is 366 divided by 400, about 92 percent of the guideline, leaving 34 mg of headroom, roughly the caffeine in one more small coffee. Your intake is equal to about 3.9 cups of coffee. Swap the tea for a second energy drink and the total jumps to about 399 mg, right on the marker.

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Frequently asked questions

How much caffeine is in a cup of coffee?

A standard cup of brewed or instant coffee has around 95 mg of caffeine on average, though it ranges widely with the beans, the brew and the cup size. This calculator uses averages of about 95 mg for coffee, 47 mg for tea, 80 mg for an energy drink and 34 mg for a cola.

How much caffeine per day is safe?

Health authorities generally regard up to 400 mg of caffeine a day as moderate for most healthy adults. During pregnancy the guideline is lower, around 200 mg a day. Children, teenagers and people sensitive to caffeine should have much less, so treat 400 mg as a general upper marker, not a target.

What are the signs of too much caffeine?

Going well over your usual intake can bring on a racing heart, jitteriness, anxiety, an upset stomach and trouble sleeping. Sensitivity varies a lot between people. If caffeine is affecting your sleep or how you feel, cutting back and having none after early afternoon usually helps.