> That’s 6-12%

"Oh no!"

> McDonald’s is known for having strong coffee

Lol.

> a double espresso from them is under 150mg

McDonalds famously does not publish caffeine numbers because they aren't forced to by the government. https://www.mcdonalds.com/us/en-us/faq/how-much-caffeine-is-...

But this person did his own measurements and says you're wrong https://www.youtube.com/watch?v=imc7Aime_cI

Anyway, here are published numbers we can find for reasonable comparison:

  Monster Energy 16oz cans
  Original Green Monster: 160 mg
  Monster Ultra / Zero Sugar: 150 mg
  Monster Lo-Carb: 140 mg

  Starbucks Brewed coffee
  Pike Place Roast: Short 155 mg, Tall 235 mg, Grande 310  mg, Venti 410 mg.
  Blonde Roast: Short 180 mg, Tall 270 mg, Grande 360 mg, Venti 475 mg.
  Dark Roast: Short 130 mg, Tall 195 mg, Grande 260 mg, Venti 340 mg.
  Decaf Pike Place: Short 15 mg, Tall 20 mg, Grande 25 mg, Venti 30 mg.

  Starbucks espresso is 150 mg per standard double shot, so e.g. a grande caramel macchiato is 150 mg for 16oz of liquid, just like the monster energy drink can.

  (In case you don't know, Grande, aka 16oz, is the most popular drink size at Starbucks, and short isn't even shown visibly on the menu.)