Coffee, decaf vs Black tea, decaf: caffeine compared
Coffee, decaf and Black tea, decaf carry the same caffeine per serving: 2 mg each. Per fluid ounce they are about the same: 0.2 mg/oz versus 0.2 mg/oz.
| Coffee, decaf | Black tea, decaf | |
|---|---|---|
| Serving | 8 oz | 8 oz |
| Caffeine per serving | 2 mg | 2 mg |
| Per fl oz | 0.2 mg | 0.2 mg |
| Share of 400 mg/day | 0% | 0% |
| Servings to reach 400 mg | 200.0 | 200.0 |
| Hours until under 50 mg | already under | already under |
| Last one for an 11 PM bedtime · standard (50 mg) | 11:00 PM | 11:00 PM |
| Last one for an 11 PM bedtime · sensitive (25 mg) | 11:00 PM | 11:00 PM |
| Share of the 200 mg pregnancy limit | 1% | 1% |
One serving of each, over 16 hours
Common questions
Which has more caffeine, Coffee, decaf or Black tea, decaf?
Neither: both have about 2 mg per serving.
Which is stronger per ounce, Coffee, decaf or Black tea, decaf?
About the same: 0.2 mg per fl oz for Coffee, decaf and 0.2 mg for Black tea, decaf. The difference per can or cup comes from serving size.
When should I stop drinking Coffee, decaf or Black tea, decaf before bed?
For an 11 PM bedtime with a 50 mg limit and a 5-hour half-life: last Coffee, decaf by 11:00 PM, last Black tea, 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, decaf: USDA FoodData Central (SR Legacy 171889), checked 2026-10-13. 1 mg per 100 g × 237 g ≈ 2 mg.
Source — Black tea, decaf: USDA FoodData Central (SR Legacy 174871), checked 2026-10-13. 1 mg per 100 g × 237 g ≈ 2 mg.