Tea Caffeine Guide: Levels Across Different Varieties

A cup of standard 240 ml black tea contains 47 mg of caffeine.

• 47 mg — 240 ml black tea (typical brewed serving).
• 70 mg — 1 tsp matcha (whole-leaf powder, per dataset).
• 85 mg — 240 ml yerba mate, one of the highest tea-type caffeine values listed.
• 0 mg — most herbal (tisanes) are caffeine-free; decaf tea and decaf coffee are near-zero.

Caffeine basics in tea

Caffeine in tea comes from the tea leaf (Camellia sinensis) and, for mate, Ilex paraguariensis. USDA FoodData Central and drink-label data provide measured averages: black tea ~47 mg per 240 ml, green tea ~28 mg per 240 ml, white tea ~16 mg per 240 ml, oolong ~37 mg per 240 ml. Matcha is measured as a 1‑teaspoon preparation with 70 mg per serving because you ingest the whole leaf powder.

Caffeine levels by tea type (measured servings)

The table below lists the dataset values for common teas and directly comparable drinks. Serving sizes are shown where they differ from the 240 ml standard.

Tea / Drink	Serving	Caffeine (mg)
Black tea	240 ml	47 mg
English Breakfast	240 ml	50 mg
Earl Grey	240 ml	47 mg
Green tea	240 ml	28 mg
White tea	240 ml	16 mg
Oolong tea	240 ml	37 mg
Matcha (1 tsp)	240 ml (standardized)	70 mg
Chai latte	240 ml	50 mg
Yerba mate	240 ml	85 mg
Iced tea (bottled)	355 ml	45 mg
Herbal tea (tisanes)	240 ml	0 mg

How tea compares to coffee and energy drinks

Tea tends to have substantially less caffeine per 240 ml than brewed coffee: drip coffee is 96 mg per 240 ml; pour-over can be higher at 145 mg per 240 ml; cold brew often measures ~200 mg per 240 ml. Espresso shots are concentrated (single shot 30 ml = 63 mg). Energy drinks vary widely (Red Bull 250 ml = 80 mg; Bang 473 ml = 300 mg). Use these numbers when substituting tea for coffee or energy drinks to estimate total daily intake.

Factors that change caffeine in tea

Measured mg values are averages—actual caffeine depends on:

• Leaf type and processing: black (fully oxidized) and yerba mate generally yield more caffeine per cup than green or white; matcha yields more because you consume the whole leaf.
• Leaf quantity and particle size: fannings/tea bags and broken leaves extract faster than whole leaves; more grams → more mg.
• Water temperature and steep time: hotter water and longer steep increase extraction. Practical rule: steep green tea shorter (1–3 min) to reduce caffeine; black tea 3–5 min extracts more.
• Serving size and concentration: bottled iced tea and lattes include variable ratios; always check serving-size labels or measure.
• Preparation method: matcha and yerba mate deliver inherently higher per-cup intake in typical preparations.

How long caffeine from tea stays in your system

Population-average caffeine half-life is about 5.7 hours; that means roughly half the caffeine remains after ~5.7 hours. Use the decay percentages below (3 h ≈ 69% remain, 6 h ≈ 48%, 9 h ≈ 33%, 12 h ≈ 23%) to estimate lingering mg from a specific cup.

Drink (dose)	0 h	3 h (≈69%)	6 h (≈48%)	9 h (≈33%)	12 h (≈23%)
Matcha — 70 mg	70 mg	48 mg	34 mg	23 mg	16 mg
Black tea — 47 mg	47 mg	32 mg	23 mg	16 mg	11 mg
Yerba mate — 85 mg	85 mg	59 mg	41 mg	28 mg	20 mg

Practical takeaway: a morning matcha (70 mg) still contributes ~34 mg at your noon coffee and ~16 mg by evening—use that when planning caffeine relative to sleep.

Health, safety and timing

Authoritative bodies set reference limits: the U.S. Food and Drug Administration and EFSA note ~400 mg/day is generally considered safe for healthy adults; many guidance documents recommend limiting caffeine to ~200 mg/day in pregnancy. The American Academy of Pediatrics advises caution and discourages caffeine-containing beverages for adolescents. Individual sensitivity varies—genetics (CYP1A2), medications, liver disease, pregnancy and age change clearance—and Mayo Clinic resources note half-life can range broadly.

If sleep is a concern, stop consuming caffeine several half-lives before bedtime. For an average half-life of 5.7 hours, avoiding caffeine 6–8 hours before bed reduces alertness effects; highly sensitive individuals may need longer.

Caffeine-free tea options and decaf

Herbal tisanes (peppermint, chamomile, rooibos) are naturally caffeine-free in the dataset (0 mg). Decaffeinated tea and decaf coffee are not totally zero but near-zero; decaf coffee is listed as 3 mg per 240 ml. Decaf tea typically contains trace amounts—check product testing if you need strict avoidance.

Track intake and next steps

For people who drink multiple cups or switch between coffee and tea, track mg across the day so totals stay within safety guidance. Apps such as CoffeeLog can automatically add dataset values and compute remaining caffeine over time using half-life to help you plan sleep and daily limits.

Sources and datasets referenced include USDA FoodData Central values for brewed teas, FDA/EFSA safety guidance, and clinical resources such as Mayo Clinic and the American Academy of Pediatrics for age- and pregnancy-related recommendations.