Black tea vs Chai latte: caffeine compared
Chai latte (16 oz) has 95 mg of caffeine, 48 mg more than Black tea (8 oz, 47 mg) — 2.0× as much per serving. Per fluid ounce they are about the same: 5.9 mg/oz versus 5.9 mg/oz.
| Black tea | Chai latte | |
|---|---|---|
| Serving | 8 oz | 16 oz |
| Caffeine per serving | 47 mg | 95 mg |
| Per fl oz | 5.9 mg | 5.9 mg |
| Share of 400 mg/day | 12% | 24% |
| Servings to reach 400 mg | 8.5 | 4.2 |
| Hours until under 50 mg | already under | 4.6 h |
| Last one for an 11 PM bedtime · standard (50 mg) | 11:00 PM | 6:22 PM |
| Last one for an 11 PM bedtime · sensitive (25 mg) | 6:27 PM | 1:22 PM |
| Share of the 200 mg pregnancy limit | 24% | 48% |
One serving of each, over 16 hours
Common questions
Which has more caffeine, Black tea or Chai latte?
Chai latte (16 oz) has about 95 mg versus 47 mg in Black tea (8 oz): 48 mg more, or 2.0× as much.
Which is stronger per ounce, Black tea or Chai latte?
About the same: 5.9 mg per fl oz for Black tea and 5.9 mg for Chai latte. The difference per can or cup comes from serving size.
How many Black tea servings equal one Chai latte?
About 2.0 servings of Black tea (8 oz) match the caffeine in one Chai latte (16 oz).
When should I stop drinking Black tea or Chai latte before bed?
For an 11 PM bedtime with a 50 mg limit and a 5-hour half-life: last Black tea by 11:00 PM, last Chai latte by 6:22 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 — Black tea: USDA FoodData Central (SR Legacy 173227), checked 2026-10-13. 20 mg per 100 g × 237 g.
Source — Chai latte: CSPI caffeine chart (Starbucks Chai Latte, 16 oz grande), checked 2026-10-13.