Estimate daily caffeine from coffee, tea, cola, energy drinks and any additional source.
Caffeine content varies by brand, cup size and preparation. Product labels provide a better figure when available.
How to use the Caffeine Calculator
Choose the relevant daily reference, then enter how many standard servings you drink in a day. Every quantity field is required, so enter 0 for items you do not consume. Add caffeine from supplements, medicines or different products in the other-caffeine field.
Estimated caffeine per serving
| Drink | Serving used | Estimated caffeine |
|---|---|---|
| Instant coffee | 1 mug | 100 mg |
| Filter coffee | 1 mug | 140 mg |
| Tea | 1 mug | 75 mg |
| Cola | 1 can | 40 mg |
| Energy drink | 250 ml | 80 mg |
Understanding the result
The percentage compares your estimate with the selected reference. It is not a personal safe-dose assessment. Sensitivity differs, and caffeine may affect sleep, anxiety, heart rate or digestion at lower amounts. Large servings and concentrated products can contain substantially more than the examples.
Caffeine during pregnancy
UK guidance advises limiting caffeine during pregnancy to no more than 200 mg a day. Caffeine can also be present in chocolate, some soft drinks, energy products and medicines, so include every source and ask a midwife, pharmacist or doctor if unsure.
Related health calculators
Track alcoholic drinks with the Alcohol Units Calculator UK, estimate body composition with the Body Fat Calculator, or plan strength training with the One Rep Max Calculator. Browse all tools on the United Kingdom Calculator homepage.
See the NHS foods to avoid in pregnancy guidance for the 200 mg daily limit and example caffeine amounts.
Frequently asked questions
Is 400 mg safe for everyone?
No. It is a general adult reference, not a personal limit. Some people experience unwanted effects at much lower amounts.
How much caffeine is advised during pregnancy?
UK guidance advises no more than 200 mg per day from all sources during pregnancy.
Why does coffee caffeine vary?
Bean type, serving size, brewing time and preparation method can substantially change the amount.
Do decaffeinated drinks contain caffeine?
They can contain a small amount. Check the product information if you need a precise total.
Does the calculator include chocolate or medicine?
Not automatically. Add their labelled caffeine amount to the other-caffeine field.