Suntory Boss Coffee vs Starbucks canned Nitro (Black): which has more caffeine?

Starbucks canned Nitro (Black) carries more total caffeine per serving (155mg per 9.6 oz can vs 140mg per 8 oz can), but ounce for ounce Suntory Boss Coffee is actually the stronger drink at about 18mg per fluid ounce against 16. Which one "has more caffeine" depends on whether you measure the container or the concentration.

Suntory Boss Coffee vs Starbucks canned Nitro (Black): the numbers

Sources: Suntory Boss Coffee's figure is verified in our Suntory Boss Coffee caffeine guide against Caffeine Informer (source); Starbucks canned Nitro (Black)'s figure is verified in our Starbucks canned Nitro (Black) guide against PepsiCo product facts (source).

Which one should you pick?

Pick Suntory Boss Coffee when you want the lighter dose or a slower ramp, and Starbucks canned Nitro (Black) 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

• Suntory Boss Coffee: the full caffeine guide
• Starbucks canned Nitro (Black): the full caffeine guide
• The verified caffeine database
• Every drink compared: the comparisons index
• Compare any two of 120+ drinks

FAQ

Does Suntory Boss Coffee or Starbucks canned Nitro (Black) have more caffeine? Starbucks canned Nitro (Black): 155mg per 9.6 oz can versus 140mg per 8 oz can for Suntory Boss Coffee.

Which is stronger per ounce? Suntory Boss Coffee, at about 17.5mg per fluid ounce versus 16.1mg for Starbucks canned Nitro (Black).