By Miles Schwartz, Founder of Bare Brew. Disclosure: we make a canned cold brew, and it is in the tables below — with its label numbers, same as everyone else's.
"Stronger" is the problem with this question, not the answer. It can mean concentration, or it can mean how much caffeine lands in your hand, and those two readings rank the same drinks in opposite orders. This page is about that conflict and how to resolve it — not about the caffeine content of any one drink.
Looking for a number rather than a comparison? If what you want is how much caffeine is in a cold brew — by brand, by size, by café — that is a different question with its own answer, and we keep it in one place: how much caffeine is in cold brew coffee. Start there and come back here for the comparison.
The short version: per fluid ounce, espresso beats everything; per serving, cold brew usually wins; and the brewing method matters less than the dose and the dilution the maker chose. Every other answer you will find picks one of those three and pretends it is the whole story. Here is all three, in one place.
The figures, and where they come from
Reference coffee figures are derived from USDA FoodData Central per-100 g caffeine values at USDA's own listed serving weights. Starbucks figures are the chain's published numbers for its standard recipes, which Starbucks itself footnotes as approximate. The canned figure for Bare Brew is our own label. All re-checked October 27, 2026.
| Drink | Serving | Caffeine per serving | Caffeine per fl oz (derived) |
|---|---|---|---|
| Espresso, single shot | 1 fl oz | ~63 mg | ~63 mg/fl oz |
| Bare Brew Cold Brew (can) | 12 fl oz | 320 mg | ~26.7 mg/fl oz |
| Starbucks Cold Brew, Tall | 12 fl oz | 155 mg | ~12.9 mg/fl oz |
| Starbucks Cold Brew, Grande | 16 fl oz | 205 mg | ~12.8 mg/fl oz |
| Drip / brewed coffee | 8 fl oz | ~95 mg | ~11.9 mg/fl oz |
| Starbucks Iced Coffee, Grande | 16 fl oz | 185 mg | ~11.6 mg/fl oz |
| Instant coffee | 8 fl oz | ~62 mg | ~7.8 mg/fl oz |
Per-fluid-ounce figures are simple division of the published serving figures — arithmetic, not a new label claim.
What the three answers actually are
1. Per fluid ounce: espresso wins, and it is not close. At roughly 63 mg in a single fluid ounce, espresso is the most concentrated common coffee drink. If "stronger" means concentration, the debate ends here — and no canned cold brew, ours included, comes near it. We took that comparison apart on its own in cold brew vs espresso.
2. Per serving: cold brew usually wins — because servings and recipes differ. A Grande cold brew (205 mg) carries more caffeine than the same-size iced coffee (185 mg) and more than double an 8 fl oz cup of drip (95 mg). That is not because cold water magically extracts more caffeine. Cold brew is typically made with a higher coffee-to-water ratio, as a concentrate, and then diluted to the maker's chosen strength. Dose and dilution decide the final number. How far apart that can land: when Consumer Reports reviewed the manufacturer-reported information for more than 40 ready-to-drink cold brews from seven brands in 2018, the caffeine figures ranged from 6 mg per fluid ounce at the low end to 25 mg per fluid ounce at the high end — a fourfold spread inside one product category. That was a review of label and manufacturer data, not laboratory testing, and it is now several years old; treat it as evidence of the spread, not as current figures. The same point, with current labels, is in our 2026 label-transcribed data for 18 products.
3. Per can, at the top end: a purpose-built canned cold brew is a different category. Our can is 320 mg in 12 fl oz — about 26.7 mg per fluid ounce, roughly double the per-fluid-ounce figure of the café cold brews above. That is a recipe choice (more coffee, no dilution to café strength), printed on the label, not a property of cold brewing itself.
The equivalence table: what 320 mg actually equals
This is the table we wish existed when people ask us "so how strong is one can, really?"
| To get ~320 mg of caffeine, you would drink about… | Amount |
|---|---|
| Drip coffee (95 mg / 8 fl oz) | ~3.4 cups — about 27 fl oz |
| Espresso (~63 mg / shot) | ~5.1 shots |
| Starbucks Cold Brew, Grande (205 mg) | ~1.6 Grandes |
| Starbucks Iced Coffee, Grande (185 mg) | ~1.7 Grandes |
| Instant coffee (62 mg / 8 fl oz) | ~5.2 cups |
| Bare Brew Cold Brew | 1 can (12 fl oz) |
For context on the size of that number: the FDA has cited 400 mg a day for most adults — about two to three 12 fl oz cups of coffee — as an amount not generally associated with negative effects. That is the FDA's framing, not a limit, a target or a recommendation, and it is not advice about you. One 320 mg can sits inside that reference figure, which is exactly why the label prints the number in large type: you should be able to do this math before you drink, not after.
So, which should you buy?
- You want the most caffeine in the fewest sips: espresso, per fluid ounce — but you will need about five shots to match a high-caffeine can.
- You want a café drink stronger than your usual iced coffee: order the cold brew at the same size; at Starbucks the published gap is 205 mg against 185 mg in a Grande. The format difference is unpacked in cold brew vs iced coffee.
- You want one grab-and-go can with the dose printed and nothing else in it: that is the case for a canned cold brew like ours. No sugar. No dairy. Bare ingredients. Special blend of coffee and water — filtered water and 100% Honduran Arabica coffee, two ingredients, 320 mg of natural caffeine, 20 calories and 5 g total carbohydrate per 12 fl oz can.
And again, for the figure rather than the comparison: how much caffeine is in cold brew coffee is the guide that answers it properly.
Bare Brew is a Newsweek Readers' Choice 2026 finalist. Find it at drinkbarebrew.com — 40+ retail placements across four states, 15 of them confirmed stocking in Michigan and Florida as of October 2026.
Figures re-checked October 27, 2026. Drip (~95 mg / 8 fl oz), espresso (~63 mg / 1 fl oz) and instant (~62 mg / 8 fl oz) are derived from USDA FoodData Central SR Legacy entries 171890, 171891 and 174130 — per-100 g caffeine values scaled at USDA's own listed serving weights. USDA's default listed serving for instant coffee is 6 fl oz; the 8 fl oz figure here is scaled from its per-fluid-ounce weight for comparability. Starbucks Cold Brew Grande 205 mg, Cold Brew Tall 155 mg and Iced Coffee Grande 185 mg are Starbucks' own published menu figures, which Starbucks footnotes as approximate values. The 6–25 mg per fluid ounce spread is from Consumer Reports' 2018 review of manufacturer-reported information for more than 40 ready-to-drink cold brews across seven brands. The 400 mg figure and its wording are from the FDA's consumer update "Spilling the Beans: How Much Caffeine is Too Much?", content current as of 08/28/2024. Café recipes change; the per-fluid-ounce and equivalence math is derived from the serving figures shown, so you can re-run it with whatever your local menu board says.
