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Coffee, brewed vs Coffee, decaf: caffeine compared

Coffee, brewed (8 oz) has 95 mg of caffeine, 93 mg more than Coffee, decaf (8 oz, 2 mg) — 47.5× as much per serving. Per fluid ounce, Coffee, brewed is the stronger drink: 11.9 mg/oz versus 0.2 mg/oz.

Coffee, brewedCoffee, decaf
Serving8 oz8 oz
Caffeine per serving95 mg2 mg
Per fl oz11.9 mg0.2 mg
Share of 400 mg/day24%0%
Servings to reach 400 mg4.2200.0
Hours until under 50 mg4.6 halready under
Last one for an 11 PM bedtime · standard (50 mg)6:22 PM11:00 PM
Last one for an 11 PM bedtime · sensitive (25 mg)1:22 PM11:00 PM
Share of the 200 mg pregnancy limit48%1%

One serving of each, over 16 hours

02550751000h2h4h6h8h10h12h14h16h50 mg bedtime limitCoffee, brewed · 95 mgCoffee, decaf · 2 mg

Common questions

Which has more caffeine, Coffee, brewed or Coffee, decaf?

Coffee, brewed (8 oz) has about 95 mg versus 2 mg in Coffee, decaf (8 oz): 93 mg more, or 47.5× as much.

Which is stronger per ounce, Coffee, brewed or Coffee, decaf?

Coffee, brewed: about 11.9 mg per fl oz versus 0.2 mg for Coffee, decaf. Serving size decides the total you actually drink.

How many Coffee, decaf servings equal one Coffee, brewed?

About 47.5 servings of Coffee, decaf (8 oz) match the caffeine in one Coffee, brewed (8 oz).

When should I stop drinking Coffee, brewed or Coffee, decaf before bed?

For an 11 PM bedtime with a 50 mg limit and a 5-hour half-life: last Coffee, brewed by 6:22 PM, last Coffee, decaf by 11:00 PM. Half-life varies from about 1.5 to 9.5 hours between people.

Method

Caffeine per labeled serving, from the same drink table every calculator here uses (FDA/USDA reference amounts and manufacturer labels; see caffeine content of every drink). Brewed drinks vary batch to batch, so read these as typical values. Decay uses a 5-hour average half-life with a 45-minute absorption ramp; cutoff = bedtime − 5 h × log₂(dose ÷ limit). Percentages use the FDA's 400 mg/day figure for healthy adults and the 200 mg/day limit ACOG gives for pregnancy.

Source — Coffee, brewed: USDA FoodData Central (SR Legacy 171890), checked 2026-10-13. 40 mg per 100 g × 237 g (8 fl oz).

Source — Coffee, decaf: USDA FoodData Central (SR Legacy 171889), checked 2026-10-13. 1 mg per 100 g × 237 g ≈ 2 mg.

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