A 1.93 fl oz bottle of 5-hour Energy, Regular Strength carries 200 mg of caffeine, 120 mg more than an 8.4 fl oz can of Red Bull Energy Drink (80 mg) - in a far smaller bottle. Per fluid ounce the gap is large: 103.63 mg/oz for 5-hour Energy, Regular Strength against 9.52 mg/oz for Red Bull Energy Drink.

Figures are each brand's own published nutrition data; see the source link in the table below. Add either one to the caffeine calculator to see how it fits your personal daily limit.

Standard serving, side by side

5-hour Energy, Regular Strength, 1.93 fl oz (57 ml) 200 mg
Red Bull Energy Drink, 8.4 fl oz (250 ml) 80 mg

Sources

Drink Serving Caffeine Source
5-hour Energy, Regular Strength 1.93 fl oz (57 ml) 200 mg 5-hour Energy, Regular Strength FAQSource
Red Bull Energy Drink 8.4 fl oz (250 ml) 80 mg Red Bull product Q&ASource