Caffeine estimate tool
Coffee Caffeine Calculator
Pick a brew method, set the serving size and brew strength, and see the estimated caffeine in that drink. Add each round to build a daily total against the 400 mg general adult reference, with the published range behind every estimate shown.
- Published ranges
- Browser-only arithmetic
- Nothing uploaded
Your day
Today's caffeine
Add a drink and it appears here. The total stacks every serving you list and compares it with the 400 mg general reference for healthy adults.
Your day
Within the 400 mg general referenceDaily caffeine total
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0 mg400 mg general reference
Drinks added
0Estimate basis
Each drink uses a published range midpoint per 100 ml, scaled by serving size and brew strength.
The 400 mg figure is a general reference, not a personal limit.
How the caffeine estimate works
Every result comes from three numbers: a published caffeine range for the brew method, the serving volume you enter, and a brew strength multiplier. The base figure is the midpoint of that range per 100 ml, so the result sits in the middle of typical brewed coffee rather than at either extreme.
- Caffeine per serving = base mg per 100 ml × (serving size ÷ 100) × strength multiplier.
- Strength multipliers = mild 0.75, medium 1.0, strong 1.25. Strength describes the brew, not the roast.
- Daily total = the per-serving estimate multiplied by the number of servings for each drink, added together.
- Reference share = daily total ÷ 400 mg. The percentage is shown for context, not as a target.
Reference ranges used
Ranges are broad because caffeine varies with dose, grind, water temperature, brew time and the coffee itself. The table shows each base figure and the range it comes from.
| Brew method | Base per 100 ml | Published range | Typical serving |
|---|---|---|---|
| Drip / filter coffee | 40 mg | 80–115 mg per 240 ml | 240 ml |
| Pour-over | 42 mg | 80–120 mg per 240 ml | 240 ml |
| French press | 46 mg | 80–135 mg per 240 ml | 240 ml |
| Espresso | 213 mg | 60–75 mg per 30 ml shot | 30 ml |
| Moka pot | 175 mg | 90–130 mg per 60 ml | 60 ml |
| Cold brew | 63 mg | 100–200 mg per 240 ml | 240 ml |
| Instant coffee | 26 mg | 50–75 mg per 240 ml | 240 ml |
| Pod / capsule coffee | 40 mg | 75–110 mg per 240 ml | 240 ml |
| Decaf coffee | 1.3 mg | 2–5 mg per 240 ml | 240 ml |
Ranges are typical figures reported for brewed coffee, espresso and instant coffee. They are not measurements of the bag, capsule or cafe drink in front of you.
Worked example: two drip coffees and one espresso
Using medium strength
- Drip coffee, 240 ml
- 40 mg per 100 ml × 2.4 × 1.0 = 96 mg
- Second drip coffee, 240 ml
- 96 mg × 1 serving = 96 mg
- Espresso, 30 ml
- 213 mg per 100 ml × 0.3 × 1.0 = 63.9 mg, shown as 64 mg
- Daily total
- 255.9 mg, shown as 256 mg — about 64% of the 400 mg general reference.
The same two coffees without the espresso come to 192 mg, or 48%. One 470 ml drip coffee at strong strength would be 235 mg on its own.
What moves the real number
- Dose and ratio. More grams of coffee per cup raises caffeine. A 20 g dose in the same 240 ml cup is stronger than a 12 g dose.
- Brew time and temperature. Longer contact and hotter water extract more caffeine. Cold brew is not automatically stronger; it depends on the concentrate ratio.
- Roast level. Dark and light roasts contain similar caffeine per bean. Dark beans lose mass in roasting, so measuring by scoop can shift the result more than roast choice does.
- Brand and capsule. Pod and capsule caffeine varies by model, blend and cup size. Use the label figure when the package provides one.
- Decaf is not zero. Decaf coffee typically keeps a small amount of caffeine, which is why it is modelled separately here.
- Milk, ice and water. Adding milk or ice changes volume and taste, not the caffeine already brewed into the coffee.
The 400 mg reference and its limits
The US Food and Drug Administration describes 400 mg of caffeine a day as an amount not generally associated with negative effects for healthy adults who are not pregnant or breastfeeding. It is a general reference, not a personal limit. Sensitivity varies, and some medications and health conditions change what is appropriate for an individual.
This calculator counts only the coffee drinks you add. Tea, soda, energy drinks, chocolate and supplements can add caffeine that is not included. It is an estimating tool, not medical advice; ask a clinician about your own intake, especially during pregnancy or if you take medication.
Frequently asked questions
How is the caffeine estimate calculated?
The calculator takes the midpoint of a published caffeine range for the brew method, per 100 ml, multiplies it by the serving volume and then by the strength multiplier. It rounds the result to the nearest milligram. The basis line under the estimate shows the exact inputs used.
Does espresso have more caffeine than drip coffee?
Per millilitre, yes. Per serving, often no: a 30 ml espresso shot is estimated at about 64 mg, while a 240 ml drip coffee is about 96 mg. A double shot or a large americano changes that comparison, so stack the actual servings you drink.
Does a darker roast have more caffeine?
Not meaningfully per bean. Roast level changes flavour and bean mass more than caffeine content. If you switch from scooping to weighing your coffee, the dose changes and that is what usually moves the number.
Is 400 mg a safe daily limit for everyone?
No single limit fits everyone. 400 mg a day is the FDA's general reference for healthy adults who are not pregnant or breastfeeding. Pregnancy, medication, heart conditions, anxiety and individual sensitivity can change the appropriate amount, so treat the reference as context and ask a clinician about your situation.
Is decaf really caffeine-free?
No. Decaffeinated coffee usually retains a small amount of caffeine, commonly reported around 2–5 mg per 240 ml. It is much lower than regular coffee, but it is not zero, so the calculator models it separately.
Why does my capsule or coffee label differ from this estimate?
A label is specific to that product and portion, while this calculator uses a broad published range for the method. If the package states caffeine per capsule or per serving, treat the label as the more specific number and use this tool to compare methods and stack drinks.
Is anything I enter saved?
No. The arithmetic runs in your browser, the drinks list stays in the page, and nothing is uploaded, stored in the URL or sent to an analytics endpoint. Refreshing the page clears the list.