Energy drink limit

Enter the caffeine on the label to see how many cans fit in a day after everything else you have had.

Your details

Who is it for?
Can size
Caffeine on the label
Other caffeine today
Sugar on the label (0 if sugar free)
Weight (only used for under 18s)

Labels give caffeine per 100 ml or per litre: 32 mg per 100 ml is 320 mg per litre. A mug of instant coffee is about 100 mg.

160 mg of caffeine a can

1 can

fit within EFSA's 400 mg for adults today

  • Your daily guide400 mg
  • Other caffeine today100 mg
  • Room left for energy drinks300 mg
  • High caffeine label needed (over 150 mg a litre)?yes
  • One can over EFSA's 200 mg single dose?no
  • Sugar in one can55 g, about 14 teaspoons and 183% of the 30 g daily free sugars maximum

Many energy drinks are also high in sugar. Mixing them with alcohol can make you feel less drunk than you are.

Get medical help if you have chest pain, a racing or irregular heartbeat or feel faint after energy drinks: call 999 for chest pain that does not go away, or 111.

The working

A 500 ml can at 320 mg a litre

500 ml at 320 mg a litre is 160 mg a can. With 100 mg already from a coffee, an adult has 300 mg left of EFSA's 400 mg guide, which fits 1 can (two would be 420 mg). For a 15 year old weighing 8 st 7 lb (54 kg), the guide is about 3 mg per kg, roughly 163 mg, so after the coffee there is no room for a whole can.

Sugar too

What the label says per 100 ml

Many full sugar energy drinks have about 11 g of sugar per 100 ml. A 500 ml can then holds 55 g, about 14 teaspoons, which is 183% of the NHS maximum of 30 g of free sugars a day for anyone aged 11 or over. Sugar free versions have the same caffeine, so the caffeine count above still applies.

The rules

What the label and the law say

  • Drinks over 150 mg of caffeine a litre must say high caffeine content, not recommended for children or pregnant or breastfeeding women
  • From April 2027 shops in England will not be allowed to sell high caffeine energy drinks to under 16s
  • EFSA says single doses up to 200 mg are not a concern for healthy adults

Worth knowing

Beyond the caffeine

  • Many energy drinks are high in sugar too; check the sugar in drinks calculator
  • Bottled tea and coffee drinks do not need the high caffeine warning if tea or coffee is in the name, so check their labels too
  • Caffeine adds up across the day, so count the coffee, tea and cola as well

Read with care

What this cannot tell you

  • Know every productUse the figure on your can.
  • Judge how you reactSome people get palpitations or anxiety on much less caffeine.
  • Replace medical advicePeople with heart conditions should ask their GP about caffeine.

Questions

Common questions

How many energy drinks a day is safe?

It depends on the can and everything else you have. A 500 ml can at 320 mg a litre is 160 mg, so most healthy adults could fit two in 400 mg only if they had no other caffeine at all.

Can teenagers drink energy drinks?

They are labelled not recommended for children, EFSA suggests under 18s keep to about 3 mg of caffeine per kg a day, and sales to under 16s in England are due to be banned from April 2027.

Are energy drinks OK in pregnancy?

The NHS limit in pregnancy is 200 mg of caffeine a day from everything. One big can can be most of that.

What does 32 mg per 100 ml mean?

It is 320 mg per litre, so a 250 ml can has 80 mg and a 500 ml can has 160 mg.

Sources

Last checked 21 October 2026. Spotted something wrong? Tell us and we will fix it.

If energy drinks are affecting you

Get medical help if you have chest pain, a racing or irregular heartbeat or feel faint: call 999 for chest pain that does not go away, or 111 for advice. If a young person is having several a day, their GP or school nurse can help.

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