Starbucks London Fog has more caffeine than Peace Tea on both counts: 40mg per 16 oz grande (40mg at every size) against 23mg per 23 oz can, and about 2mg per fluid ounce against 1. The serving sizes differ, so the table below shows both ways of counting.
Starbucks London Fog vs Peace Tea: the numbers
| Starbucks London Fog | Peace Tea | |
|---|---|---|
| Caffeine per serving | 40mg per 16 oz grande (40mg at every size) | 23mg per 23 oz can |
| Caffeine per fl oz | 2.5mg | 1.0mg |
| Servings to reach 400mg (FDA context) | 10.0 | 17.4 |
Sources: Starbucks London Fog's figure is verified in our Starbucks London Fog caffeine guide against Starbucks nutrition listing (source); Peace Tea's figure is verified in our Peace Tea guide against Caffeine Informer (source).
Which one should you pick?
Pick Peace Tea when you want the lighter dose or a slower ramp, and Starbucks London Fog when you actually need the bigger hit and know your tolerance. If you are stacking either with other caffeinated drinks through the day, run the math against the 400mg reference rather than guessing.
For context, the FDA cites 400mg of caffeine a day as an amount generally not associated with negative effects in healthy adults. Tolerance and health vary, so treat these numbers as information, not advice.
Related reading
- Starbucks London Fog: the full caffeine guide
- Peace Tea: the full caffeine guide
- The verified caffeine database
FAQ
Does Starbucks London Fog or Peace Tea have more caffeine? Starbucks London Fog: 40mg per 16 oz grande (40mg at every size) versus 23mg per 23 oz can for Peace Tea.
Which is stronger per ounce? Starbucks London Fog, at about 2.5mg per fluid ounce versus 1.0mg for Peace Tea.
Comparing caffeine? The caffeine comparison tool puts hundreds of drinks side by side, and the caffeine curfew calculator can check your cutoff time for tonight.