Caffeine in drinks
How much caffeine is in Milky Way?
Sources checked claim by claim by an AI review. Approved for publishing by Oleksii Y. on 2026-10-19.
One 2.05 oz bar (58 g) of Milky Way has 3.5 mg of caffeine, according to USDA Agricultural Research Service, FoodData Central (SR Legacy).
How Milky Way compares
- Strength: 6 mg per 100 g.
- One 2.05 oz bar (58 g) has as much caffeine as less than a sixth of a cup of brewed coffee, which has 94.8 mg per 8 fl oz cup.
- Of the 9 other candy bars and chocolate candies in our candy bars chart, 6 have more caffeine per serving and 3 have less.
How much will be left at bedtime?
1 × 2.05 oz bar (58 g) of Milky Way
Left at 11:00 PM (8 h later), average metabolism
≈ 1.2 mg
Range 0.6–1.8 mg (fast to slow metabolism)
3.5 mg is already at or under the 50 mg this tool aims to have left at bedtime.
Estimate from a simple model: half-life of 3, 5 or 8 hours, 50 mg bedtime target. How we calculate
Caffeine by size
| Serving | Caffeine |
|---|---|
| 2.05 oz bar (58 g) | 3.5 mg |
| 1.76 oz Milky Way Midnight bar (50 g) | 15 mg |
How long does Milky Way stay in your system?
Our model halves caffeine every 5 hours for average metabolism, and every 3 or 8 hours for fast or slow metabolism. From one 2.05 oz bar (58 g) of Milky Way (3.5 mg), about 1.8 mg is still in your body 5 hours later and about 0.9 mg after 10 hours. If you clear caffeine slowly (an 8-hour half-life), about 1.5 mg is left after 10 hours.
Estimated caffeine left at 11:00 PM from one 2.05 oz bar (58 g) (3.5 mg), using a half-life of 5 hours for average metabolism and 3 to 8 hours for the range. How we calculate
| Had at | Left at bedtime (average) | Range |
|---|---|---|
| 8:00 AM (15 h before bed) | ≈ 0.4 mg | 0.1–1 mg |
| 12:00 PM (11 h before bed) | ≈ 0.8 mg | 0.3–1.3 mg |
| 3:00 PM (8 h before bed) | ≈ 1.2 mg | 0.6–1.8 mg |
| 6:00 PM (5 h before bed) | ≈ 1.8 mg | 1.1–2.3 mg |
How many fit in a day?
Reference amounts are for caffeine from all sources combined. Counted at the upper end of the stated amount, one serving at a time:
- Up to 400 mg a day for most healthy adults (FDA, EFSA): about 114 servings.
- Up to 200 mg at one time for healthy adults (EFSA): about 57 servings in one go.
- Up to 200 mg a day in pregnancy (EFSA, NHS): about 57 servings.
These are reference amounts for groups of people, not a personal limit. Some people feel jittery or sleep worse on much less. See the cutoff calculator for timing.
Good to know
Per 100 g, USDA's estimate for Milky Way Midnight is five times the regular Milky Way's (30 mg against 6 mg).
How the serving amount was worked out: USDA estimate: 6 mg per 100 g for Milky Way and 30 mg per 100 g for Milky Way Midnight, both calculated from the ingredient list; 58 g × 0.06 = 3.48 mg, rounded to 3.5 mg; 50 g × 0.30 = 15 mg.
Common questions
How much caffeine is in Milky Way?
USDA Agricultural Research Service, FoodData Central (SR Legacy) gives 3.5 mg of caffeine per 2.05 oz bar (58 g). Other sizes are in the table on this page.
How many Milky Way servings can I have in a day?
The FDA and EFSA cite up to 400 mg of caffeine a day, from all sources combined, for most healthy adults. At 3.5 mg per 2.05 oz bar (58 g), that is about 114 servings if Milky Way is your only source. In pregnancy the reference is 200 mg a day.
How late can I drink Milky Way?
One serving has about 3.5 mg, which is at or under the 50 mg our calculator aims to have left at bedtime, so it sets no cutoff for a single serving. Several servings add up.
How long does Milky Way stay in your system?
Of the 3.5 mg in one 2.05 oz bar (58 g), roughly 1.8 mg remains after 5 hours and 0.9 mg after 10 hours with our average 5-hour half-life. From fast to slow metabolism, 10 hours later it is between 0.3 and 1.5 mg.
Where the number comes from
- Candies, MARS SNACKFOOD US, MILKY WAY Bar. USDA Agricultural Research Service, FoodData Central (SR Legacy). FDC ID 168756, nutrient "Caffeine" (262): 6 mg per 100 g, derivation FLA (estimated formulation); portion "serving 2.05 oz bar" = 58 g. Milky Way's own site (milkywaybar.com) gave no caffeine figure we could read on 2026-10-13, so these numbers are USDA's. Accessed 2026-10-09. Source ↗
- Candies, MARS SNACKFOOD US, MILKY WAY Midnight Bar. USDA Agricultural Research Service, FoodData Central (SR Legacy). FDC ID 167701, nutrient "Caffeine" (262): 30 mg per 100 g, derivation FLA; portion "serving 1.76 oz bar" = 50 g. Accessed 2026-10-09. Source ↗
Recipes and labels change. If a number here no longer matches the label, the label wins.
General information, not medical advice
If you feel unwell after caffeine — for example chest pain, a fast or irregular heartbeat that does not settle, fainting, confusion or trouble breathing — get urgent medical help. If you are pregnant or breastfeeding, under 18, take medication, or have a heart, liver or anxiety condition, high blood pressure or a sleep disorder, ask a doctor or pharmacist what amount is right for you.
Sources
- U.S. Food and Drug Administration (2024). Spilling the Beans: How Much Caffeine is Too Much? FDA Consumer Updates. fda.gov ↗
- European Food Safety Authority. Caffeine | EFSA. EFSA topic page (summary of the 2015 Scientific Opinion on the safety of caffeine). efsa.europa.eu ↗
- NHS. Foods to avoid in pregnancy. NHS. nhs.uk ↗
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