For most adults, daily intake above 400 mg, or large doses taken close together, can push caffeine into a danger zone with fast-rising side effects.

A typical 8-oz mug of dark roast brewed coffee lands near 95 mg of caffeine, with real-life cups often ranging from 70–140 mg.

An 8-oz mug of brewed coffee often lands near 80–100 mg of caffeine, yet roast, grind, and brew time can swing it wide.

An 8-oz cup of Earl Grey tea often lands around 30–60 mg of caffeine, with the swing driven by leaf amount, steep time, and water heat.

A standard 8-oz cup of Lipton black tea lands near 55 mg of caffeine, with steep time and tea type shifting the total.

A standard 8-oz mug of brewed black tea often lands near 40–50 mg of caffeine, with green and white teas lower.

A typical cup of instant coffee has 30–90 mg caffeine, varying by brand, scoop size, and water volume.

A standard 8-fl-oz cup of Mountain Dew lands near 36 mg of caffeine when the soda matches the 54 mg per 12-oz can label.

A regular 8-oz strong brewed coffee often lands around 120–200 mg of caffeine, with beans, dose, and brew time driving the swing.

A standard Starbucks brewed coffee lands around 210–325 mg of caffeine, mostly driven by cup size and roast.