Tea vs Coffee Caffeine: How Much Caffeine Is in Each Cup?
Author: Ukrainian Psychological Hub · Published: September 29, 2026 · Editorial Policy
Coffee usually contains more caffeine per serving than brewed tea. The difference is large enough to be useful as a rule of thumb, but there is no single caffeine number for either drink. Cup size, coffee brew method, the amount of tea or coffee used, steep time, water temperature, and the specific product can all change the dose.
For a direct comparison, Health Canada lists an average of 135 mg of caffeine in an 8-fluid-ounce (237 mL) cup of brewed coffee and 30–50 mg in the same volume of brewed black or green tea. The U.S. Food and Drug Administration gives another useful reference point for 12-fluid-ounce servings: 113–247 mg for regular brewed nonspecialty coffee, 71 mg for black tea, and 37 mg for green tea.
Those figures are not contradictory. They come from different reference datasets and serving sizes, and that is exactly why the most accurate answer to “tea vs coffee caffeine” is a range rather than a universal number.
Tea vs Coffee Caffeine: The Quick Answer
If you compare ordinary brewed drinks in the same cup size, coffee generally has substantially more caffeine than black tea or green tea.
For an 8-ounce cup, Health Canada’s reference values are:
Coffee, brewed: about 135 mg on average.
Black or green tea, brewed: about 30–50 mg.
Coffee can therefore provide roughly two to four times as much caffeine as an ordinary brewed black or green tea in that reference comparison. The ratio is not fixed. A weak coffee and a strong, long-steeped tea can move closer together, while a large filter coffee can contain far more caffeine than a small cup of tea.
For 12 ounces, the FDA lists:
Regular brewed nonspecialty coffee: 113–247 mg.
Black tea: 71 mg.
Green tea: 37 mg.
The practical conclusion is simple: if caffeine dose is the main question, start with serving size and preparation, not just the word “tea” or “coffee.”
For a tea-only comparison across black, green, oolong, white, matcha, herbal, and decaffeinated options, see Caffeine in Tea: Black, Green, Matcha, Oolong, White, and Herbal Tea Compared. For the broader sensory and daily-routine comparison, see Tea vs Coffee: Caffeine, Taste, Focus, Ritual, and Which Feels Different.
Why “How Much Caffeine Is in a Cup?” Has More Than One Correct Number
A cup is a container, not a standardized caffeine dose.
An 8-ounce cup, a 12-ounce café drink, a 16-ounce travel mug, a double espresso, and a teacup brewed from two tea bags may all be described casually as “a cup.” They can contain very different amounts of caffeine.
The FDA explicitly notes that caffeine content varies by product and container size. Older analytical work also found large variation in coffee and tea caffeine concentration and showed that steeping time materially affected tea caffeine extraction. More recent laboratory work continues to find that brewing time, temperature, tea type, and serving format can change caffeine in the finished infusion. In other words, the uncertainty is part of the beverage itself, not merely a problem with nutrition charts.
This matters for search comparisons because two apparently precise claims can both be accurate if one refers to 8 ounces and the other to 12 or 16 ounces. Whenever you compare tea and coffee, normalize the serving volume first.
Caffeine in Coffee: Brew Method and Serving Size Matter
Coffee is not one caffeine dose.
Health Canada reports an average of 135 mg for 8 ounces of brewed coffee, but its more specific figures range from 76–106 mg for 8 ounces of instant coffee to 179 mg for 8 ounces of filter-drip coffee. Percolated coffee is listed at 118 mg per 8 ounces.
Commercial coffee can vary even more. An analytical study of specialty coffees found a wide range in caffeinated servings and substantial day-to-day variation in the same beverage from the same outlet. That study is older, so it should not be used as a current menu guide, but it remains a useful demonstration of why café coffee should not be treated as a fixed chemical dose. The current FDA caffeine guidance similarly advises consumers to check product information because actual amounts and sizes vary.
Brewed Coffee
Brewed coffee usually dominates a tea-vs-coffee comparison because coffee beverages commonly contain more caffeine per serving. The exact amount depends on bean characteristics, coffee-to-water ratio, grind, extraction, brew method, and serving size.
A larger cup does not merely look bigger; if concentration is similar, it delivers a larger total caffeine dose. This is why comparing a 16-ounce coffee with an 8-ounce tea tells you as much about portion size as it does about the plants.
For a full coffee-side breakdown, including roast, bean, brew method, and serving size, see How Much Caffeine Is in Coffee? Bean, Roast, Brew, Serving Size, and Why Effects Vary.
Espresso
Espresso creates a common comparison trap. It is concentrated, so it can contain more caffeine per ounce than drip coffee, but a standard espresso serving is much smaller. A full mug of brewed coffee may therefore contain more total caffeine than one espresso shot.
The useful question is “How many milligrams are in the serving I will drink?” rather than “Which beverage is more concentrated?”
Instant and Decaf Coffee
Instant coffee often contains less caffeine than filter-drip coffee in standardized comparisons, although products vary. Decaffeinated coffee is lower in caffeine, but “decaf” does not necessarily mean caffeine-free. The FDA states that decaf coffee typically contains 2–15 mg in an 8-ounce cup.
That residual amount is small compared with ordinary brewed coffee, yet it can matter to someone who is highly sensitive to caffeine or intentionally limiting total intake.
Caffeine in Tea: Black, Green, Matcha, Oolong, White, and Herbal Drinks
Tea is also not a single caffeine category.
True tea from Camellia sinensis naturally contains caffeine, but the finished cup depends on the leaf, amount used, processing, particle size, brewing conditions, and serving format. A 2008 analysis of 20 commercial teas found 14–61 mg per 6- or 8-ounce serving across white, green, and black teas, with steep time affecting caffeine concentration and no simple variety-based ranking that worked across every product. That study supports an important point: color labels alone do not let you calculate the caffeine in a particular cup.
Black Tea
Black tea usually contains less caffeine per cup than brewed coffee, while often containing more than a typical green tea reference value. The FDA’s 12-ounce reference values are 71 mg for black tea and 113–247 mg for regular brewed nonspecialty coffee.
A stronger black tea, more leaf, a tea bag with small particles, or a longer steep can increase extraction. Yet black tea remains a beverage with substantial product-to-product variation, so “black tea has exactly X mg” is too precise for the category.
For a broader comparison of these two drinks beyond caffeine quantity, see Black Tea vs Coffee: Caffeine, Alertness, Taste, and Daily Routine.
Green Tea
Green tea also contains caffeine. Health Canada groups brewed black and green tea at an average range of 30–50 mg per 8 ounces, while the FDA gives a typical 12-ounce green-tea figure of 37 mg.
The apparent mismatch is another reminder that authorities use different datasets and reference servings. Neither figure should be read as a laboratory guarantee for your particular sencha, gunpowder, jasmine green tea, bottled product, or tea bag.
For the broader drink comparison, see Green Tea vs Coffee: Caffeine, Focus, Taste, and Daily Routine.
Matcha
Matcha requires a separate explanation because the powdered tea is consumed rather than discarded after infusion. Its caffeine dose depends strongly on the amount of matcha powder in the serving. A small serving made with a modest amount of powder and a large café matcha drink made with more powder are not equivalent.
That makes a single universal “matcha caffeine” number especially misleading. Matcha can overlap with stronger brewed teas and, depending on preparation, can approach some coffee servings, but it does not automatically contain more caffeine than coffee.
For a dedicated comparison that also covers focus, anxiety-like sensations, taste, and ritual, see Matcha vs Coffee: Caffeine, Focus, Anxiety, Taste, and Ritual.
Oolong and White Tea
Oolong and white tea contain caffeine because they are made from Camellia sinensis. Their caffeine cannot be inferred reliably from color or oxidation level alone. Leaf material, cultivar, particle size, dose, and brewing method all matter.
A recent laboratory study comparing several tea types found meaningful differences under controlled conditions and also found that longer brewing could substantially increase caffeine extraction. The study is useful for mechanism and variability, but its exact laboratory values should not be treated as universal retail serving values. The lesson is about what changes extraction, not a permanent ranking of every white, oolong, green, and black tea.
Herbal Tea
Most herbal infusions are not made from Camellia sinensis and do not naturally contain tea caffeine. The 2008 analytical study cited above detected no caffeine in the herbal products it tested.
Still, “herbal tea” on a package does not guarantee zero caffeine if the blend contains true tea, yerba mate, guarana, or another caffeinated ingredient. Check the ingredient list when caffeine avoidance is important.
Which Has More Caffeine: Tea Leaves or Coffee Beans?
This popular question often produces a technically interesting but practically confusing answer.
Dry tea leaves can contain substantial caffeine by weight. That does not mean a prepared cup of tea necessarily contains more caffeine than a prepared cup of coffee. You typically use different amounts of plant material, different water-to-solid ratios, different extraction methods, and different serving sizes for the two drinks.
The consumer question is therefore about the finished beverage. In ordinary prepared servings, coffee usually delivers more total caffeine than brewed black or green tea, as the FDA and Health Canada reference values show.
Comparing dry leaf with dry coffee is chemistry. Comparing a cup of tea with a cup of coffee is exposure.
What Changes the Caffeine in Tea?
The caffeine in tea is partly a property of the leaf and partly a property of preparation.
Research on tea infusions has identified several relevant variables. A study of black and green tea found that variety, growing environment, manufacturing conditions, leaf grade, tea-bag characteristics, amount of tea and water, infusion time, and agitation can all influence the composition of the brewed drink. A 2025 chromatographic study likewise found effects of tea type, brewing time, temperature in some conditions, and serving method.
Amount of Tea
Using more tea for the same amount of water generally gives the brew access to more caffeine. Two tea bags in one mug are not equivalent to one tea bag simply because the mug size is unchanged.
Steep Time
Longer steeping generally allows more caffeine to move from leaf into water, although the extraction curve is not perfectly linear forever. The 2008 brewed-tea analysis found steep time affected caffeine concentration, and controlled brewing studies have continued to show time-dependent extraction.
This means “steep it for less time to reduce caffeine” has a reasonable chemical basis, but it is not a precision dosing method. Product differences can be larger than the effect you are trying to create.
Water Temperature
Hotter water can change extraction. The magnitude depends on tea and preparation conditions. Temperature also affects many flavor compounds, so changing it alters the sensory cup as well as its chemistry.
Particle Size and Tea Bags
Smaller particles expose more surface area. Some bagged teas therefore extract rapidly. The relationship is product-specific rather than a rule that every tea bag contains more caffeine than every loose-leaf tea.
Re-Steeping
Later infusions can still contain caffeine. The amount remaining depends on what was extracted in earlier steeps, the leaf, water temperature, steep duration, and ratio. A second steep is not automatically caffeine-free.
What Changes the Caffeine in Coffee?
Coffee caffeine likewise varies before and during brewing.
Bean species and blend can matter, as can the mass of coffee used, grind size, water volume, brew time, extraction method, and final serving size. Café recipes add another source of variation because the same drink name may be sold in multiple sizes or with different numbers of espresso shots.
This is one reason caffeine comparisons should use milligrams per actual serving rather than stereotypes such as “dark roast is stronger” or “espresso has the most caffeine.” Per-ounce concentration, total serving dose, and sensory intensity are different concepts.
A coffee can taste dark, bitter, or intense without having the highest caffeine dose. A tea can taste light while still containing meaningful caffeine. Flavor intensity is not a caffeine meter.
Is the Caffeine in Tea Different From the Caffeine in Coffee?
The caffeine molecule is the same.
The FDA states that there is no difference in how the body handles or in the safety of naturally occurring caffeine from sources such as coffee and tea compared with added caffeine. The beverage surrounding the caffeine can differ, but “tea caffeine” is not a separate chemical species with a fundamentally different stimulant mechanism.
What can differ is the dose, the beverage matrix, the speed and pattern of drinking, accompanying compounds, habitual use, expectation, and the context in which the drink is consumed.
That distinction explains why two drinks can feel different without inventing two kinds of caffeine.
Why Tea and Coffee Can Feel Different Even When Both Contain Caffeine
Subjective experience is not determined by caffeine content alone.
A large coffee may deliver a bigger caffeine dose than tea, which can produce a more noticeable stimulant effect. But two servings with closer caffeine amounts can still be experienced differently because perception integrates pharmacology, expectation, taste, temperature, pace, familiarity, and context.
Caffeine Dose and Interoception
Caffeine stimulates the central nervous system. EFSA describes moderate doses as increasing alertness and reducing sleepiness. People also perceive bodily signals differently. Heart rate, muscle tension, gastrointestinal sensations, warmth, and wakefulness can be noticed, ignored, interpreted as useful activation, or interpreted as uncomfortable overstimulation.
That does not mean the sensations are imaginary. It means subjective experience is the brain’s interpretation of real internal signals in context.
Expectation Can Shape the Experience
Expectancy is one reason beverage labels and habits matter. In a controlled study, Harrell and Juliano manipulated what participants were told to expect from coffee and found that expectancy influenced some subjective and behavioral responses to caffeine.
This finding does not imply that expectation replaces caffeine pharmacology. Caffeine still has measurable effects. It shows that the felt experience of a stimulant is produced by both pharmacological input and psychological interpretation.
A person who associates coffee with “powerful energy” and tea with “calm focus” may enter each drink with a different prediction. Those predictions can color attention to bodily sensations and performance.
Tea, L-Theanine, and the “Calm Energy” Claim
Tea contains L-theanine, and this has generated a common internet claim that tea always produces smoother, calmer, or longer-lasting energy than coffee.
The evidence is more specific. A 2014 systematic review and meta-analysis found some acute attentional benefits from combinations of caffeine and L-theanine. A larger 2025 systematic review and meta-analysis of randomized trials found small-to-moderate differences favoring theanine plus caffeine for some cognitive and mood outcomes, while confidence intervals often reflected uncertainty. Importantly, the authors called for more research using actual tea beverages or tea-equivalent doses and free-living participants.
So it is reasonable to say that caffeine-plus-theanine has evidence for some short-term cognitive outcomes. It is not reasonable to turn that into a guarantee that every brewed tea produces “calm energy,” prevents jitters, or releases caffeine slowly. Evidence from isolated compounds and laboratory preparations cannot simply be transferred to every cup of tea.
Tea vs Coffee for Alertness and Focus
Caffeine can improve aspects of attention acutely in healthy adults.
A 2025 systematic review and meta-analysis of randomized, double-blind, placebo-controlled trials found small improvements in both reaction-time and accuracy measures after pure caffeine. Higher doses showed larger reaction-time effects, while accuracy did not improve indefinitely with dose.
That evidence is about pure caffeine under controlled conditions. It does not prove that a particular coffee is cognitively “better” than a particular tea. In daily life, the caffeine dose in the serving, baseline sleepiness, tolerance, withdrawal reversal, task, timing, and individual response all influence how a drink feels and how performance changes.
Coffee often delivers more caffeine per cup, so it may create a stronger acute stimulant effect. That can be useful when a larger dose is wanted, but more caffeine is not automatically better performance. A higher dose can also increase unwanted effects in susceptible people.
Tea may provide a smaller, easier-to-titrate caffeine dose for someone who wants mild alertness. That is a dose-management advantage, not proof of a special universally superior form of focus.
Tea vs Coffee, Jitters, Nervousness, and Anxiety
Caffeine can produce nervousness, jitters, and anxiety-like sensations, especially at higher doses and in sensitive individuals. The FDA lists anxiety and jitters among possible signs of excessive caffeine intake.
A 2024 meta-analysis in healthy populations found higher anxiety ratings after caffeine, with a stronger effect at higher doses. The included evidence was heterogeneous, and much of it involved caffeine doses that are higher than a typical cup of tea.
This distinction matters. Feeling temporarily keyed up after caffeine is a symptom or subjective state; it is not by itself a diagnosis of an anxiety disorder. Tea or coffee should not be described as causing or treating a clinical anxiety disorder on the basis of ordinary beverage comparisons.
Because coffee commonly contains more caffeine per serving, switching from a large coffee to a lower-caffeine tea can reduce caffeine dose. Whether that reduces uncomfortable arousal for a particular person depends on the actual products, serving sizes, total daily caffeine, and individual sensitivity.
If significant anxiety symptoms are persistent or impairing, the clinical question is broader than choosing between tea and coffee.
Tea vs Coffee and Sleep
The relevant substance for sleep is caffeine regardless of whether it came from tea or coffee.
A 2023 systematic review and meta-analysis found that caffeine reduced total sleep time, lowered sleep efficiency, increased sleep-onset latency, and increased wake time after sleep onset. The analysis also showed that dose and timing matter. Its modeled guidance suggested that a 107 mg coffee should be consumed about 8.8 hours before bedtime to avoid a reduction in total sleep time on average.
That number is not a universal personal cutoff. It is a population-level estimate derived from the available studies. Individual metabolism, habitual intake, dose, age, medications, pregnancy, and sensitivity can shift the effect.
Tea may be easier to fit later in the day when it contains less caffeine than the coffee it replaces, but caffeinated tea is not automatically “safe for sleep.” A strong black tea, matcha, multiple tea servings, or late-day green tea still contributes to total caffeine exposure.
The useful sleep question is not “Is tea good for sleep?” It is “How much caffeine am I getting, and how close to bedtime am I drinking it?”
How Much Caffeine Is Too Much?
For most adults, the FDA cites 400 mg of caffeine per day as an amount not generally associated with negative effects. Health Canada also lists 400 mg per day as its recommended maximum for adults.
That is a population-level benchmark, not a target and not a guarantee that 399 mg will feel comfortable to everyone. The FDA emphasizes wide variation in caffeine sensitivity and elimination. Some people experience sleep disruption, palpitations, jitters, headache, or gastrointestinal symptoms at lower intakes.
Pregnancy, breastfeeding, medications, and some health conditions require more individualized guidance. The FDA advises discussing caffeine limits with a health care professional in those situations. Different authorities also use somewhat different pregnancy guidance, which is another reason not to turn a general tea-versus-coffee article into personal medical dosing advice.
If you are tracking caffeine, count all sources across the day: coffee, tea, matcha, energy drinks, cola, chocolate, supplements, and some medications.
A Practical Way to Compare Your Own Tea and Coffee
The most useful comparison is the one you actually drink.
Start with serving size. Write down the volume of the mug or café size rather than calling everything “one cup.”
Then identify preparation. For coffee, note brewed, filter, instant, espresso-based, cold brew, or another method. For tea, note black, green, matcha, oolong, white, or herbal, plus the amount of leaf or powder and steep time.
Use manufacturer or café caffeine information when available. Category averages are useful when product data are unavailable, but they cannot replace a product-specific measurement.
Count repeated servings. Two 50 mg teas equal 100 mg of caffeine; a single 150 mg coffee is 150 mg. Habitual patterns matter more than beverage labels.
Finally, connect dose with your actual outcome. If your concern is sleep, record timing. If your concern is jitters, note total caffeine and whether the beverage was consumed quickly, on an empty stomach, or after a period of low caffeine use. If your goal is attention, notice whether a larger dose improves the task or simply creates stronger bodily arousal.
This turns “tea versus coffee” from a brand identity question into a measurable caffeine question.
Common Tea vs Coffee Caffeine Myths
“Tea has less caffeine because tea leaves contain less caffeine”
The finished beverage depends on extraction and how much material is used. Dry-leaf chemistry does not directly predict cup-level exposure. Prepared coffee generally contains more caffeine per serving than ordinary brewed tea in authoritative reference tables.
“Coffee always has exactly twice as much caffeine as tea”
There is no fixed ratio. Health Canada’s 8-ounce averages and the FDA’s 12-ounce values show broad category differences, but products and methods overlap.
“Black tea always has more caffeine than green tea”
Black tea often appears higher in reference tables, yet analytical studies show enough product and brewing variation that tea color alone cannot reliably rank every individual cup.
“Espresso has more caffeine than brewed coffee”
Espresso is highly concentrated per ounce. Total caffeine per serving may still be lower than a full mug of brewed coffee because the serving is much smaller.
“Decaf means zero caffeine”
Not necessarily. The FDA reports that decaf coffee typically contains 2–15 mg per 8 ounces. Decaffeinated tea is also much lower in caffeine than regular tea, but product values can vary.
“Tea caffeine is chemically gentler”
Caffeine is the same molecule. Tea contains other compounds and is often consumed at a lower caffeine dose, and expectation and ritual can shape experience. Those differences do not create a different form of caffeine.
“L-theanine cancels caffeine jitters”
Current evidence does not establish that every tea serving neutralizes caffeine-related arousal. Controlled studies of theanine plus caffeine show some cognitive and mood effects, but they cannot be converted into a universal anti-jitter claim for brewed tea.
“A darker or stronger-tasting drink has more caffeine”
Sensory intensity and caffeine dose are not the same property. Roast character, bitterness, astringency, aroma, temperature, concentration, milk, and sugar can change perceived strength without providing a reliable caffeine measurement.
Frequently Asked Questions
Does tea have more caffeine than coffee?
Usually no when comparing ordinary prepared servings of the same volume. Health Canada lists about 135 mg for 8 ounces of brewed coffee and 30–50 mg for 8 ounces of brewed black or green tea. Product and brewing variation can narrow or widen the gap.
How much caffeine is in an 8-ounce cup of tea versus coffee?
Health Canada lists 30–50 mg for 8 ounces of brewed black or green tea and an average of 135 mg for 8 ounces of brewed coffee. Filter-drip coffee is listed higher at 179 mg per 8 ounces, while instant coffee is listed at 76–106 mg.
How much caffeine is in a 12-ounce tea versus coffee?
The FDA gives typical values of 37 mg for 12 ounces of green tea, 71 mg for black tea, and 113–247 mg for regular brewed nonspecialty coffee.
Does black tea have less caffeine than coffee?
Usually yes per ordinary serving. The FDA’s 12-ounce reference is 71 mg for black tea versus 113–247 mg for regular brewed nonspecialty coffee. Strong preparation, unusual serving sizes, and specific products can change the comparison.
Does green tea have less caffeine than coffee?
Generally yes. The FDA lists 37 mg in a typical 12-ounce green tea compared with 113–247 mg in 12 ounces of regular brewed nonspecialty coffee.
Is matcha more caffeinated than coffee?
Not necessarily. Matcha caffeine depends heavily on how much powder is used. Some matcha servings are more caffeinated than ordinary green tea, but coffee commonly remains higher per serving. Compare product-specific milligrams whenever possible.
Which tea has the most caffeine?
There is no permanent winner across all products. Black tea often ranks high in reference tables, while matcha can be substantial because the powder is consumed. Controlled analyses show that leaf characteristics, amount used, particle size, time, temperature, and format can change the result enough that tea type alone is an imperfect predictor.
Does steeping tea longer increase caffeine?
Generally, longer steeping allows more caffeine extraction. Analytical studies of brewed tea have found steep-time effects. The exact increase depends on the tea and brewing conditions.
Does adding milk reduce caffeine?
Adding milk changes volume, taste, texture, and perceived strength but does not remove the caffeine already extracted into the drink. If milk displaces some tea or coffee in a fixed-size beverage, the total caffeine can be lower because there is less caffeinated liquid, not because milk chemically removes the caffeine.
Is herbal tea caffeine-free?
Many pure herbal infusions are naturally caffeine-free because they are not made from Camellia sinensis. Blends may still contain true tea, yerba mate, guarana, or other caffeine sources, so check ingredients.
Is decaf coffee caffeine-free?
No. The FDA states that decaf coffee typically contains 2–15 mg of caffeine per 8-ounce cup.
Is caffeine from tea absorbed more slowly than caffeine from coffee?
The internet often describes tea as having “slow-release caffeine,” but that phrase overstates the evidence. The caffeine molecule is the same. Beverage composition, dose, drinking pace, food, and individual physiology can affect the time course and subjective experience, while L-theanine research mainly concerns specific compound combinations rather than proof of a unique slow-release mechanism in every cup of tea.
Which is better for focus, tea or coffee?
There is no universal winner. Caffeine can acutely improve some attention outcomes, but the optimal dose varies. Coffee usually provides a larger caffeine dose; tea often provides a smaller one. The better fit depends on the task, baseline sleepiness, tolerance, desired stimulation, and sensitivity to unwanted effects.
Which is better if caffeine makes me jittery?
A lower-caffeine serving may be easier to tolerate, and ordinary tea often contains less caffeine than coffee. The important variable is the actual caffeine dose, not the beverage label. Persistent or severe symptoms warrant a broader health discussion rather than a beverage-only solution.
Can tea still affect sleep?
Yes. Caffeinated tea contributes to total caffeine exposure. Lower caffeine may reduce the dose compared with coffee, but timing and sensitivity still matter.
Bottom Line
Coffee usually has more caffeine per cup than brewed tea. In Health Canada’s 8-ounce reference, brewed coffee averages 135 mg while brewed black or green tea contains 30–50 mg. In the FDA’s 12-ounce reference, regular brewed coffee contains 113–247 mg, black tea 71 mg, and green tea 37 mg.
The exact amount in your drink can differ substantially. Serving size, coffee brew method, tea dose, steep time, temperature, particle size, and product formulation all matter. Matcha deserves its own calculation because the powder is consumed. Herbal infusions are often caffeine-free but blends can contain caffeinated ingredients. Decaf is lower in caffeine rather than automatically caffeine-free.
Tea and coffee can also feel different for reasons that extend beyond the milligram count. Dose, habitual use, expectation, interoception, pace of drinking, flavor, ritual, and other tea compounds can influence subjective experience. The strongest evidence still supports a simple starting point: caffeine is caffeine, and the most reliable comparison begins with the amount in the actual serving.
Related Articles
References
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