How much caffeine is in cold brew? It depends mostly on how strong it's brewed and how much it's diluted: a cup made from concentrate mixed half and half with water or milk has roughly 115 to 145 mg per 8 oz, and a 16 oz glass about 230 to 290 mg. That's well above an 8 oz mug of hot brewed coffee (about 95 mg). Undiluted concentrate is stronger still.
Ready-to-drink bottles and cans vary so much that the label is the only reliable number. When you have it, plug it into the caffeine calculator to see how much will be left at bedtime.
Free toolCaffeine Cutoff CalculatorHow much caffeine is still in you at bedtime, and your latest cup.How much caffeine is in cold brew?
In a lab study of cold brew made at 1 part coffee to 10 parts water, caffeine came out at about 990 to 1,230 mg per liter after 24 hours, depending on the roast and grind. That's about 29 to 36 mg per ounce of undiluted brew.
For comparison, USDA data puts regular hot brewed coffee at about 40 mg per 100 grams, or roughly 12 mg per ounce. So a 1:10 cold brew is about 2.5 to 3 times as strong per ounce as a normal cup of coffee.
Here's what that means per serving, using the study's range:
| Cold brew serving | Caffeine |
|---|---|
| 4 oz concentrate, undiluted | 117 to 146 mg |
| 8 oz cup (4 oz concentrate + 4 oz water or milk) | 117 to 146 mg |
| 8 oz concentrate, undiluted | 234 to 291 mg |
| 16 oz glass (8 oz concentrate + 8 oz water or milk) | 234 to 291 mg |
| For comparison: hot brewed coffee, 8 oz | about 95 mg |
Water, milk and ice add no caffeine. They only spread it out. What you drink is whatever concentrate went into the glass.
Concentrate vs ready-to-drink cold brew
Concentrate is made to be diluted, while ready-to-drink cold brew is already diluted and meant to be poured straight. Mixing them up is the most common way people get far more caffeine than they planned.
- Concentrate: often brewed at a strong ratio like the 1:10 in the study, then cut with water or milk, commonly 1:1. Drinking it straight doubles your dose.
- Ready-to-drink: brewed or diluted to drinking strength. Caffeine still varies a lot between brands and bottle sizes, so check the label.
- Coffee-shop cold brew: usually concentrate plus water and ice. Shops differ in their ratio, and a large cup can hold a lot of concentrate.
- Homemade: you control it. Less coffee per cup of water, or more dilution, means less caffeine.
Does cold brew have more caffeine than hot coffee?
Per cup, usually yes, but mainly because cold brew is made stronger, not because cold water pulls out more caffeine. When the same researchers brewed the same coffee at the same 1:10 ratio with hot water, the hot versions had about 840 to 1,060 mg per liter, compared with 990 to 1,230 mg for cold brew.
Cold brew came out higher in every comparison, but the gap was only statistically clear for coarse-ground coffee. For medium grinds, hot and cold were close. Medium roasts tended to give more caffeine than dark roasts, though not every difference was significant.
The study also found that caffeine was mostly extracted within about 6 to 7 hours. Steeping for 12 to 24 hours changes the flavor, but adds little extra caffeine.
How much caffeine is in iced coffee?
USDA lists brewed iced coffee at 31 mg per 100 grams, which works out to about 74 mg in 8 oz, 112 mg in a small (about 12 oz) and 149 mg in a medium (about 16 oz). USDA models it as 12 oz of hot brewed coffee poured over a cup of ice, so the ice dilutes it slightly compared with hot coffee.
| Iced coffee size | Caffeine |
|---|---|
| 8 fl oz | about 74 mg |
| Small, about 12 fl oz | about 112 mg |
| Medium, about 16 fl oz | about 149 mg |
| Large, about 20 fl oz | about 186 mg |
So for the same cup size, iced coffee is usually milder than cold brew. An iced latte is a different drink: it's espresso over ice, so count about 63 mg per shot, as in how much caffeine is in espresso.
Latest cold brew or iced coffee before bed
For a 10:30 PM bedtime, finish a 16 oz cold brew by about 5:30 AM and a 16 oz iced coffee by about 9:35 AM. These use the site's caffeine math: an average 5-hour half-life, and the time it takes a drink to fall below about 25 mg by bedtime. Cold brew figures use the middle of the study range.
| Drink | Caffeine | Bedtime 10:00 PM | Bedtime 10:30 PM | Bedtime 11:00 PM |
|---|---|---|---|---|
| Iced coffee, 8 oz | 74 mg | 2:10 PM | 2:40 PM | 3:10 PM |
| Iced coffee, 12 oz | 112 mg | 11:10 AM | 11:40 AM | 12:10 PM |
| Iced coffee, 16 oz | 149 mg | 9:05 AM | 9:35 AM | 10:05 AM |
| Cold brew, 8 oz (half concentrate) | 130 mg | 10:05 AM | 10:35 AM | 11:05 AM |
| Cold brew, 16 oz (half concentrate) | 263 mg | 5:00 AM | 5:30 AM | 6:00 AM |
A big cold brew is effectively a first-thing-in-the-morning drink. Even at 7 AM, a 16 oz glass still leaves about 31 mg at 10:30 PM.
How much is left at 10:30 PM depends on when you drink it:
| Drink at | Iced coffee, 16 oz | Cold brew, 8 oz | Cold brew, 16 oz |
|---|---|---|---|
| 7:00 AM | 17 mg | 15 mg | 31 mg |
| 9:00 AM | 23 mg | 20 mg | 40 mg |
| 11:00 AM | 30 mg | 26 mg | 53 mg |
| 1:00 PM | 40 mg | 35 mg | 70 mg |
| 3:00 PM | 53 mg | 46 mg | 93 mg |
| 5:00 PM | 70 mg | 61 mg | 123 mg |
People clear caffeine at different speeds, so if you're sensitive, treat these times as too late. For the hour-by-hour picture, see how long caffeine lasts.
How to keep cold brew from costing you sleep
Make cold brew a morning drink, and dilute it more if you want it later. A few simple swaps:
- Order a small, or ask for extra water or milk. More dilution, less caffeine per glass.
- Switch to iced coffee after lunch. A small iced coffee has roughly half the caffeine of a 16 oz cold brew.
- Count the whole day. A 16 oz cold brew can be more than half of the 400 mg daily limit usually quoted for healthy adults. How much caffeine is too much shows how it adds up.
- Compare drinks side by side in the caffeine in drinks chart.