Comprehensive Guide to Tea Caffeine Levels

Caffeine levels by tea type

The dataset below lists common teas with exact caffeine amounts per serving. These are measured-per-serving values used by food databases and beverage manufacturers; small recipe or steep-time differences will move the numbers.

How tea compares to coffee and energy drinks

Teas generally deliver less caffeine per 240 ml than brewed coffee and many energy drinks. For reference, drip coffee (240 ml) in the dataset is 96 mg, cold brew (240 ml) = 200 mg, and a typical energy drink (250–473 ml) ranges from 80 mg to 300 mg. Yerba mate and strong matcha come closest to a light brewed coffee.

Why caffeine numbers vary: brewing, leaf and format

Leaf type and processing

Black, oolong, green and white all come from Camellia sinensis; processing changes polyphenols and soluble caffeine extraction. Generally: black (oxidized) ≈ the dataset value 47 mg/240 ml, oolong lower (37 mg), green lower still (28 mg) and white lowest (16 mg).

Preparation variables

Steep time, water temperature, leaf quantity and leaf particle size matter. Longer steeps and hotter water extract more caffeine; matcha is powdered whole leaf so a 1 tsp matcha infusion gives the whole-leaf caffeine (70 mg per 240 ml in the dataset) rather than a fraction.

Tea blends and concentrates

Chai lattes use black tea plus milk and spices (50 mg/240 ml here). Bottled iced teas are often brewed then diluted—dataset shows 45 mg per 355 ml.

Caffeine decay: how much remains hours after drinking

Use the population-average half-life of 5.7 hours to estimate remaining caffeine. An approximate rule: after ~3 h ≈ 69% remains, 6 h ≈ 48%, 9 h ≈ 33%, 12 h ≈ 23%.

Example: if you drink a matcha (70 mg) at 3 pm, expect ~34 mg remaining by 9 pm — enough to affect sleep in sensitive people.

Health and safety context

Recommended limits

For healthy adults, the FDA and many authorities cite about 400 mg/day as a safe upper bound. For pregnancy, expert guidance (including EFSA and Mayo Clinic summaries) suggests limiting to about 200 mg/day. The American Academy of Pediatrics discourages routine caffeine for adolescents.

Symptoms and caution

Watch for heart palpitations, anxiety, insomnia, or gastrointestinal upset. Very high daily totals (several hundred milligrams beyond recommended limits) raise overdose risk; seek medical care for severe symptoms. For personalized advice, consult your clinician.

Practical tips for lowering or tracking intake

• Choose white or green tea to cut caffeine: white tea = 16 mg/240 ml, green = 28 mg/240 ml.
• Use shorter steeps and cooler water to reduce extraction.
• For a no-caffeine alternative, pick herbal tisanes (0 mg in dataset).
• Track servings and totals with an app like CoffeeLog to automatically sum mg/day and compare to the 400 mg guideline.

Regional and cultivar differences (what "Assam" or "Darjeeling" means for caffeine)

Region, cultivar and harvest (first flush vs later flush) change leaf chemistry. Black Assam or English Breakfast blends often lean toward the higher end of black tea values (the dataset lists English Breakfast at 50 mg/240 ml). Darjeeling and single-origin green teas typically yield lower caffeine than robust black blends.

Bottom line

"Tea caffeine content" spans roughly 0–85 mg in common servings: white tea about 16 mg, green 28 mg, black around 47–50 mg, matcha 70 mg and yerba mate 85 mg. Use the decay numbers above and guideline limits (≈400 mg/day for adults, ≈200 mg/day pregnancy) to plan timing and total daily intake.

Track daily totals and timing with CoffeeLog to see how a cup at 3 pm affects evening caffeine remaining.

How do I calculate remaining caffeine after several teas spaced across a day?

Calculate each cup separately with the decay formula and add the survivors; the total remaining at any time is the sum of remaining milligrams from every dose. For example, using the population-average half-life of 5.7 hours (the decay model used on this page), you can estimate remaining caffeine precisely.

First-order elimination is a decay process where the rate of removal is proportional to the current amount of caffeine.

Use the formula remaining mg = D × 0.5^(hours / 5.7). Example: drink Black tea (47 mg) at 09:00, Matcha (70 mg) at 14:00 and Green tea (28 mg) at 17:00 and check remaining at 22:00.

Black tea: hours = 13; factor = 0.5^(13/5.7) = 0.5^2.2807 ≈ 0.2058 → 47 × 0.2058 ≈ 9.7 mg. Matcha: hours = 8; factor = 0.5^(8/5.7) = 0.5^1.4035 ≈ 0.3786 → 70 × 0.3786 ≈ 26.5 mg. Green tea: hours = 5; factor = 0.5^(5/5.7) = 0.5^0.8772 ≈ 0.544 → 28 × 0.544 ≈ 15.2 mg.

Sum the survivors: 9.7 + 26.5 + 15.2 ≈ 51.4 mg remaining at 22:00. If you prefer a calculator, try our caffeine half-life calculator to enter doses and times and get the same arithmetic automatically.

How much caffeine do a matcha plus a brewed black tea add up to — and is that near safe daily limits?

A matcha (70 mg per 240 ml) plus a standard black tea (47 mg per 240 ml) totals 117 mg of caffeine consumed. That combined dose is well below the 400 mg/day upper bound cited by the FDA.

Cumulative intake is the sum of individual doses consumed over the day.

Arithmetic: 70 mg (Matcha) + 47 mg (Black tea) = 117 mg total. After about 6 hours, remaining would be roughly 70 × 0.5^(6/5.7) ≈ 34 mg from the matcha and 47 × 0.5^(6/5.7) ≈ 23 mg from the black tea, leaving ~57 mg in your system 6 hours later.

For context, the U.S. Food and Drug Administration sets ≈400 mg/day as a general safe upper bound for healthy adults; use our matcha guide and black tea guide if you need product-specific values.

Can tea caffeine interact with medications or make heart conditions worse?

Yes—caffeine can alter medication effects or exacerbate certain heart conditions, so check with your clinician if you take prescription drugs or have arrhythmia. EFSA's 2015 opinion also highlights that single large doses matter clinically and recommends caution for high single doses.

Drug–caffeine interaction is when caffeine changes a medication’s effect or its clearance from the body.

Practical notes: EFSA's 2015 Scientific Opinion flags 200 mg as a relevant single-dose threshold and recommends limits for special populations; clinicians often advise closer monitoring for people on stimulants, certain antidepressants, or antiarrhythmic drugs. The Mayo Clinic and other clinical resources list common interactions and advise consulting a prescriber about caffeine when starting or changing medications.

If you use caffeine pills (200 mg) or concentrated pre-workout scoops (200 mg in the dataset), mention those exact doses to your clinician; our caffeine overdose and teenage safety guides cover situations that commonly require medical advice.

When should I stop drinking tea so it won’t disrupt my sleep?

To reduce sleep disruption, avoid substantial caffeine within several hours of bedtime because measurable sleep lost can occur even when only a fraction of the dose remains. Drake et al. (2013) found that 400 mg taken 6 hours before bedtime reduced objective sleep time by over an hour, so apply the same timing logic scaled to your doses.

Sleep interference is measurable reduction in sleep time or quality caused by stimulant intake.

Example timing arithmetic with the 5.7 h half-life: a 240 ml black tea (47 mg) consumed 6 hours before bedtime leaves 47 × 0.5^(6/5.7) ≈ 47 × 0.482 ≈ 22.7 mg still active at lights-out. A matcha (70 mg) 6 hours before bed leaves ≈34 mg. For highly sensitive sleepers, even 20–30 mg in the system near bedtime can fragment sleep.

Use our latest cup before bedtime tool to enter your planned bedtime and get the recommended last-cup time based on these decay numbers.

How does the caffeine concentration of bottled iced tea compare to a 240 ml brewed cup?

Bottled iced tea in the dataset is 355 ml with 45 mg of caffeine, while a 240 ml brewed black tea is 47 mg; bottled iced tea is larger but less concentrated. Calculating mg per 100 ml shows the concentration difference.

Serving size is the beverage volume used to report caffeine content.

Arithmetic: bottled iced tea = 45 mg ÷ 355 ml × 100 ≈ 12.7 mg/100 ml; brewed black tea = 47 mg ÷ 240 ml × 100 ≈ 19.6 mg/100 ml. That means a 240 ml cup of black tea contains roughly the same total caffeine as a larger 355 ml bottled iced tea because the bottled drink is more dilute.

For brand-specific bottled values, see our caffeine in iced tea brands guide; for a tea-to-coffee comparison, try the side-by-side drink comparison.

Bottom line

Common tea servings in the dataset span 0–85 mg per serving: White tea ~16 mg/240 ml, Green tea ~28 mg/240 ml, Black tea ~47–50 mg/240 ml, Matcha (1 tsp) 70 mg/240 ml, and Yerba mate 85 mg/240 ml. Use the population-average half-life of 5.7 hours (342 minutes) to convert dose into what's left hours later with the formula remaining = D × 0.5^(hours/5.7); for example, 47 mg × 0.5^(6/5.7) ≈ 22.7 mg remains after 6 hours.

The U.S. Food and Drug Administration's guidance sets roughly 400 mg/day as an upper bound for healthy adults and EFSA's 2015 Scientific Opinion highlights 200 mg as a clinically meaningful single dose and the pregnancy limit of about 200 mg/day; compare your totals to those figures when planning intake. If you need quick checks, use our caffeine half-life calculator and last-cup-before-bed tool so you can see cumulative mg and timing at a glance.

Practical takeaway: a single matcha (70 mg) plus a black tea (47 mg) total 117 mg — well under the 400 mg FDA daily bound — but timing still matters because tens of milligrams can remain into the evening. When medication, pregnancy, adolescence or heart conditions are relevant, discuss exact dataset doses (for example, 200 mg caffeine pills or 85 mg yerba mate) with your clinician and consult the pregnancy and safety guides linked on this site.