WellByNumbers.

Celsius vs Ghost Energy: caffeine compared

Celsius and Ghost Energy carry the same caffeine per serving: 200 mg each. Per fluid ounce, Celsius is the stronger drink: 16.7 mg/oz versus 12.5 mg/oz.

CelsiusGhost Energy
Serving12 oz16 oz
Caffeine per serving200 mg200 mg
Per fl oz16.7 mg12.5 mg
Share of 400 mg/day50%50%
Servings to reach 400 mg2.02.0
Hours until under 50 mg10.0 h10.0 h
Last one for an 11 PM bedtime · standard (50 mg)1:00 PM1:00 PM
Last one for an 11 PM bedtime · sensitive (25 mg)8:00 AM8:00 AM
Share of the 200 mg pregnancy limit100%100%

One serving of each, over 16 hours

0501001502000h2h4h6h8h10h12h14h16h50 mg bedtime limitCelsius · 200 mgGhost Energy · 200 mg

Common questions

Which has more caffeine, Celsius or Ghost Energy?

Neither: both have about 200 mg per serving.

Which is stronger per ounce, Celsius or Ghost Energy?

Celsius: about 16.7 mg per fl oz versus 12.5 mg for Ghost Energy. Serving size decides the total you actually drink.

When should I stop drinking Celsius or Ghost Energy before bed?

For an 11 PM bedtime with a 50 mg limit and a 5-hour half-life: last Celsius by 1:00 PM, last Ghost Energy by 1:00 PM. Half-life varies from about 1.5 to 9.5 hours between people.

Method

Caffeine per labeled serving, from the same drink table every calculator here uses (FDA/USDA reference amounts and manufacturer labels; see caffeine content of every drink). Brewed drinks vary batch to batch, so read these as typical values. Decay uses a 5-hour average half-life with a 45-minute absorption ramp; cutoff = bedtime − 5 h × log₂(dose ÷ limit). Percentages use the FDA's 400 mg/day figure for healthy adults and the 200 mg/day limit ACOG gives for pregnancy.

Source — Celsius: CSPI caffeine chart (Celsius, 12 oz), checked 2026-10-13.

Source — Ghost Energy: GHOST Energy 16 fl oz can (label as listed by Target), checked 2026-10-13. Brand site does not state the amount on its product page.

More comparisons