Caffeine Content by Drink: Gyokuro, Green Tea, Black Tea, Energy Drinks and Decaf
Here is a list of the caffeine content of everyday drinks and foods: coffee, green tea, black tea, energy drinks, cola, chocolate and more. Amounts per 100 ml and per cup give very different impressions, so "green tea has less caffeine than coffee" and "gyokuro has more caffeine than coffee" can both be true. Based on official figures such as Japan's Standard Tables of Food Composition, this article sets out the caffeine in each drink, how long one serving takes to clear, how many energy drinks are too many, and the difference between decaf, caffeine-reduced and caffeine-free labels.
Caffeine per 100 ml
First, here are the amounts compared at the same 100 ml. Tea and coffee figures are for brewed tea and coffee from Japan's Standard Tables of Food Composition (8th edition), which are also used in materials from Japan's Ministry of Agriculture and Food Safety Commission. Cola and energy drinks are typical product values.
| Drink | Per 100 ml | Compared with coffee |
|---|---|---|
| Gyokuro | 160 mg | About 2.7 times |
| Drip coffee | 60 mg | Baseline |
| Instant coffee (2 g powder in 140 ml) | 57 mg | About the same |
| Canned coffee | 50–60 mg (varies a lot by product) | About the same |
| Energy drinks | 32–40 mg (depends on product) | About half to 2/3 |
| Black tea | 30 mg | Half |
| Sencha, hojicha, oolong tea | 20 mg | 1/3 |
| Cola | About 11 mg | About 1/5 |
| Bancha, genmaicha | 10 mg | 1/6 |
| Barley tea, rooibos, corn tea | 0 mg | None |
Per 100 ml, gyokuro is far ahead of everything else, and sencha, hojicha and oolong tea have a third of coffee's caffeine. You sometimes hear that hojicha is low in caffeine, but the food composition table gives the same 20 mg as sencha. Roasting doesn't reduce it much, so if you want to avoid caffeine, choose something like barley tea.
Caffeine per serving and how long it takes to clear
Compare by the amount you actually drink and the order changes. The time to clear is how long it takes, for a typical person with a 5-hour half-life who has just one serving, for the amount in the body to fall to 50 mg or less (including absorption time).
| Drink (serving size) | Caffeine | Time until 50 mg or less |
|---|---|---|
| Energy drink 355 ml | About 142 mg | 7 h 48 min |
| Canned coffee 185 g | About 102 mg | 5 h 23 min |
| Caffeine tablet / stay-awake pill, 1 tablet (100 mg) | 100 mg | 5 h 16 min |
| Oolong tea 500 ml (plastic bottle) | About 100 mg | 5 h 16 min |
| Gyokuro 60 ml | About 96 mg | 4 h 58 min |
| Drip coffee 150 ml | About 90 mg | 4 h 30 min |
| Espresso, 1 shot | About 80 mg | 3 h 39 min |
| Energy drink 250 ml | About 80 mg | 3 h 39 min |
| Instant coffee 140 ml | About 80 mg | 3 h 38 min |
| Matcha (1 bowl of thin tea, 2 g powder) | About 64 mg | 2 h 2 min |
| Energy tonic 100 ml | About 50 mg | 50 mg or less from the start |
| Black tea 150 ml | About 45 mg | 50 mg or less from the start |
| Cola 350 ml | About 39 mg | 50 mg or less from the start |
| Dark chocolate 50 g | About 25 mg | 50 mg or less from the start |
| Sencha or hojicha 120 ml | About 24 mg | 50 mg or less from the start |
| Milk chocolate 50 g | About 10 mg | 50 mg or less from the start |
| Decaf coffee 150 ml | Up to about 9 mg | 50 mg or less from the start |
Bottled oolong and green tea may be low per 100 ml, but a whole bottle can hold around 100 mg, sometimes more than a cup of coffee. The longer your half-life, the longer it takes to clear: with an 8-hour half-life, one cup of drip coffee takes about 7 hours and a 355 ml energy drink about 12 hours. How to calculate this is explained in how long caffeine takes to wear off.
Why gyokuro and matcha are high in caffeine
Gyokuro and matcha (or rather tencha, the leaf it's ground from) are grown with the tea bushes covered to block sunlight for a period before picking. This produces leaves rich in caffeine as well as theanine, the compound behind their savoury taste. Gyokuro is then brewed strong, with plenty of leaves and a small amount of lukewarm water, giving 160 mg per 100 ml, well above coffee.
- Gyokuro: servings are small (about 60 ml), so one cup has about 96 mg, roughly the same as a cup of coffee
- Matcha: the whole leaf is ground and drunk, so one bowl of thin tea (2 g powder) has about 64 mg. Thick tea or matcha lattes that use more powder contain more
- Sencha: ordinary green tea grown in sunlight. One cup (120 ml) has about 24 mg, about a quarter of coffee
- Cold-brewed green tea: less caffeine is extracted at low temperatures, so it's lower than tea made with hot water
Drinking gyokuro or a matcha latte at night on the assumption that "it's just tea" affects sleep about as much as coffee. If you want something before bed, barley tea is a better choice than hojicha. Cut-off times by drink are explained in how many hours before bed to stop drinking coffee.
How many energy drinks a day?
Caffeine varies a lot between energy drinks, from around 80 mg in a 250 ml can to 140 mg or more in a 355 ml can. The side of the can says "caffeine X mg" or "X mg per 100 ml", so always check.
| Product type | Caffeine per can | Within an adult's 400 mg a day | Within 200 mg at once |
|---|---|---|---|
| 250 ml, 32 mg/100 ml | About 80 mg | 5 cans | 2 cans |
| 355 ml, 40 mg/100 ml | About 142 mg | 2 cans (2.8) | 1 can |
| 500 ml, 40 mg/100 ml | About 200 mg | 2 cans | 1 can |
These counts assume you drink nothing else. If you had 2 cups of coffee (about 180 mg) in the morning, one 355 ml energy drink brings the total to about 322 mg. For children the guideline is 2.5 mg per kg of body weight a day, so a child weighing 40 kg has a limit of 100 mg, exceeded by a single 355 ml can. Limits for different groups are collected in daily caffeine limits.
Decaf, caffeine-reduced and caffeine-free: what's the difference?
The labels you see when cutting down on caffeine look similar but mean different things. Here's how they are used in Japan.
| Label | Meaning | Caffeine |
|---|---|---|
| Decaf | Coffee beans or tea leaves that naturally contain caffeine, with the caffeine removed | A little remains |
| Caffeine-less (caffeine-reduced) | For coffee in Japan, used for products with at least 90% of the caffeine removed | 1/10 of normal or less |
| Non-caffeine / caffeine-free | Made from ingredients that never contained caffeine, like barley tea or rooibos | None |
| Caffeine zero | Indicates no caffeine, or an undetectable amount | Practically 0 |
Decaf and caffeine-reduced coffee aren't zero; a cup of drip coffee may still contain up to about 9 mg. That's still a tenth or less of regular coffee (about 90 mg), so its effect at night or during pregnancy is considered small. For choosing drinks in pregnancy and breastfeeding, see also caffeine during pregnancy and breastfeeding.
Caffeine in cola, chocolate and medicines
- Cola: about 39 mg in a 350 ml can. Zero-calorie colas contain caffeine too (except caffeine-free products)
- Chocolate: found in cacao; about 25 mg in 50 g of dark chocolate and about 10 mg in 50 g of milk chocolate. The higher the cacao content, the more caffeine
- Cocoa: made from cacao, so it contains a small amount
- Energy tonics: many 100 ml bottles contain around 50 mg
- Cold medicine, headache medicine and stay-awake pills: some contain "anhydrous caffeine". Some stay-awake pills contain 100 mg or more per dose
See the drink chart in the tool
- 1
Open the "Caffeine by Drink" tab
For 20 drinks, you can see the caffeine per serving, how many servings fit within 400 mg and 200 mg, and the time until the amount falls below your target.
- 2
Change the half-life and target amount
Change the half-life (your constitution) or the bedtime target (25, 50 or 100 mg) and the times to clear are recalculated for those conditions.
- 3
Enter today's drinks and check the amount at night
Enter what you've drunk in the "Today's Intake & Bedtime" tab to see how many mg will be left at bedtime and the latest time for one more cup.
FAQ
- Which has more caffeine, green tea or coffee?
- Per 100 ml, drip coffee has 60 mg and sencha 20 mg, so coffee has three times as much. Per serving too, coffee (about 90 mg in 150 ml) has about four times as much as sencha (about 24 mg in 120 ml). But gyokuro has 160 mg per 100 ml, more than coffee, and a 500 ml bottle of green tea can contain around 100 mg.
- How much caffeine is in gyokuro?
- Japan's Standard Tables of Food Composition give 160 mg per 100 ml of brewed gyokuro, about 2.7 times coffee. Servings are small, about 60 ml, so one cup has about 96 mg, roughly the same as a cup of coffee. Drinking it at night affects sleep about as much as coffee.
- Is hojicha low in caffeine?
- According to the food composition table, brewed hojicha has 20 mg per 100 ml, the same as sencha. That's more than bancha or genmaicha (10 mg), so it can't really be called low in caffeine. If you want to avoid caffeine, choose drinks made without tea leaves, such as barley tea, rooibos or corn tea.
- Does decaf contain caffeine?
- Only a little. Decaf and caffeine-reduced coffee have at least 90% of the caffeine removed, but a cup of drip coffee may still contain up to about 9 mg. If you want it to be completely zero, choose caffeine-free drinks made from ingredients that never contained caffeine.
- Which has more caffeine, an energy drink or coffee?
- Per 100 ml, drip coffee (60 mg) has more than energy drinks (32–40 mg). But because cans are large, a 355 ml can has about 142 mg, more than 1.5 times a cup of coffee (about 90 mg). Amounts vary by product, so check the label on the can.
Tools in this article
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