Latte vs Flat white: caffeine compared
Latte (16 oz (2 shots)) has 150 mg of caffeine, 20 mg more than Flat white (12 oz, 130 mg) — 1.2× as much per serving. Per fluid ounce, Flat white is the stronger drink: 10.8 mg/oz versus 9.4 mg/oz.
| Latte | Flat white | |
|---|---|---|
| Serving | 16 oz (2 shots) | 12 oz |
| Caffeine per serving | 150 mg | 130 mg |
| Per fl oz | 9.4 mg | 10.8 mg |
| Share of 400 mg/day | 38% | 32% |
| Servings to reach 400 mg | 2.7 | 3.1 |
| Hours until under 50 mg | 7.9 h | 6.9 h |
| Last one for an 11 PM bedtime · standard (50 mg) | 3:05 PM | 4:06 PM |
| Last one for an 11 PM bedtime · sensitive (25 mg) | 10:05 AM | 11:06 AM |
| Share of the 200 mg pregnancy limit | 75% | 65% |
One serving of each, over 16 hours
Common questions
Which has more caffeine, Latte or Flat white?
Latte (16 oz (2 shots)) has about 150 mg versus 130 mg in Flat white (12 oz): 20 mg more, or 1.2× as much.
Which is stronger per ounce, Latte or Flat white?
Flat white: about 10.8 mg per fl oz versus 9.4 mg for Latte. Serving size decides the total you actually drink.
How many Flat white servings equal one Latte?
About 1.2 servings of Flat white (12 oz) match the caffeine in one Latte (16 oz (2 shots)).
When should I stop drinking Latte or Flat white before bed?
For an 11 PM bedtime with a 50 mg limit and a 5-hour half-life: last Latte by 3:05 PM, last Flat white by 4:06 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 — Latte: Starbucks — Caffè Latte nutrition (Grande), checked 2026-10-13.
Source — Flat white: Starbucks — Flat White nutrition (Tall 12 oz), checked 2026-10-13.