A typical 8 oz (240 ml) cup of brewed coffee has about 95–100 mg of caffeine.

Quick Scoop

  • Standard brewed coffee (8 oz): about 95–100 mg caffeine.
  • Range for brewed coffee: roughly 80–120 mg per 8 oz, depending on beans and brew method.
  • Espresso: about 60–65 mg per 1 oz shot.
  • Instant coffee (8 oz): about 60–70 mg.
  • Cold brew (8–12 oz): roughly 100–200 mg, often higher than regular coffee.
  • Decaf coffee (8 oz): usually 2–15 mg, not zero.

Why the numbers vary

  • Bean type (Robusta has almost double the caffeine of Arabica).
  • Roast level (light roast is slightly higher in caffeine per scoop than dark roast).
  • Grind size and brew time (finer grinds and longer contact time pull out more caffeine).
  • Serving size (a “cup” at a café is often 12–16 oz, so total caffeine can easily exceed 200–300 mg).

Simple rule of thumb

If you think in “normal mugs” rather than lab-sized cups:

  • A small home mug (8–10 oz) of regular coffee ≈ 90–120 mg caffeine.
  • A larger café cup (12–16 oz) of drip coffee ≈ 150–300+ mg, depending on the brand and brew.

Bottom line: when someone asks “how many mg of caffeine in coffee,” the safest quick answer is “about 100 mg per small cup, but it can go much higher depending on size and style.”

Information gathered from public forums or data available on the internet and portrayed here.