Caffeine in coffee vs tea vs green tea: how much is in your cup?
UpdatedA 200 ml cup of instant or filter coffee contains about 90 mg of caffeine, a single espresso about 80 mg, a 250 ml cup of black tea about 55 mg and a 250 ml cup of green tea about 38 mg. The NHS uses rounder estimates: about 100 mg in a cup of instant coffee and about 75 mg in a cup of tea. The real amount in your cup can be quite different, because it depends on the beans or leaves, how strong it is brewed and the size of the cup.
Key points
• Coffee usually has the most caffeine per cup, then espresso, black tea and green tea.
• A cup of tea: about 55–75 mg of caffeine, depending on the source and cup size.
• Brewing time, strength and cup size change the amount a lot.
• Tea also contains L-theanine, an amino acid; coffee does not.
• All caffeine counts towards the same daily total: up to 400 mg a day for adults (FSA and Food Standards Scotland).
Table of contents
- Caffeine per cup compared
- Why the amount varies
- Is green tea better than coffee?
- L-theanine: what tea has and coffee doesn't
- How caffeine pouches compare
- FAQ
Caffeine per cup compared
| Drink | Serving | Caffeine |
|---|---|---|
| Instant coffee | 200 ml cup | about 90 mg |
| Filter coffee | 200 ml cup | about 90 mg |
| Espresso | single shot | about 80 mg |
| Black tea | 250 ml cup | about 55 mg |
| Green tea | 250 ml cup | about 38 mg |
Work out your own total: caffeine calculator.
Source: EUFIC, Caffeine levels in different foods and drinks. The NHS estimates about 100 mg for a cup of instant coffee and about 75 mg for a cup of black or green tea.
More on single drinks: Caffeine in a cup of coffee · Caffeine in an espresso · Caffeine in green tea and Earl Grey · Caffeine in matcha · Caffeine in decaf coffee · Caffeine in chai
Why the amount varies
- Strength: more coffee or tea per cup means more caffeine.
- Brewing: longer brewing and hotter water extract more caffeine, especially from tea.
- Cup size: coffee shop cups are often much bigger than 200 ml.
- Beans and leaves: different coffee beans and tea leaves contain different amounts of caffeine.
Because of this, the figures above are averages. A large coffee shop coffee can contain much more than a cup made at home.
Coffee shop coffee varies the most: one study of single espressos bought from 20 coffee shops in Glasgow found between 51 mg and 322 mg of caffeine per shot (Crozier et al., Food & Function, 2012).
Brewing time matters for tea too: in a 2025 study, longer brewing increased both the caffeine and the L-theanine in the cup (Ayakdaş and Ağagündüz, Foods, 2025).
Is green tea better than coffee?
It depends on what you are comparing. On caffeine, a cup of green tea usually contains less than half the caffeine of a cup of coffee. Both are low in calories when drunk without milk and sugar. Which one suits you is a personal choice; the caffeine in both counts towards the same daily total. For more options, see Coffee alternatives in the UK.
L-theanine: what tea has and coffee doesn't
Tea leaves naturally contain L-theanine, an amino acid. In one study, a 314 ml cup of black tea made with a 2 g tea bag contained about 25 mg of L-theanine (van der Pijl et al., Journal of Functional Foods, 2010). Coffee does not contain L-theanine. More on this: L-theanine and caffeine: what they are.
How caffeine pouches compare
A caffeine pouch is not a drink: it sits under your upper lip for 20–40 minutes. Optimal Native pouches state the caffeine per pouch on the label:
- Morning Energy: 200 mg caffeine, with L-theanine 50 mg
- Daily Flow: 75 mg caffeine, with L-theanine 50 mg
- Evening Relax: caffeine-free, with L-theanine 100 mg
Not recommended for children or pregnant or breast-feeding women. Do not exceed the stated recommended daily dose. Optimal Native sells only to adults aged 18 and over.
FAQ
How much caffeine is in a cup of tea?
About 55 mg in a 250 ml cup of black tea (EUFIC); the NHS estimates about 75 mg for a cup of tea. Stronger or longer-brewed tea contains more.
Does tea have more caffeine than coffee?
Per cup, usually not. A 250 ml cup of black tea has about 55 mg, while a 200 ml cup of coffee has about 90 mg.
How much caffeine is in green tea?
About 38 mg in a 250 ml cup, depending on the leaves and brewing.
Does decaf coffee contain caffeine?
Yes, a small amount: about 4 mg per 200 ml cup. More: How much caffeine is in decaf?
How many cups of coffee is 400 mg?
At about 90 mg per 200 ml cup, roughly four cups. See How much caffeine is too much?
Read more: Caffeine pouches in the UK · Caffeine in matcha vs coffee · Coffee pouches: what they are
Optimal Native is coming to the UK. One stack for the whole day: Morning Energy, Daily Flow and Evening Relax. Pre-orders ship from 15 December 2026.