The brain weighs about how many pounds?

The brain weighs about how many pounds?

• A. 2 pounds
• B. 4 pounds
• C. 3 pounds
• D. 5 pounds

Answer: (C)

The brain weighs about 3 pounds. In adults, the typical brain mass is roughly 1.3–1.4 kilograms, which converts to about 2.9–3.1 pounds, commonly rounded to 3 pounds. That’s the standard estimate most people memorize. The other values are noticeably off for an average adult brain: 2 pounds is lighter than the usual range, while 4 or 5 pounds would be heavier than what most adult brains weigh. Remember that there is some individual variation, but 3 pounds is the go-to approximation.

The brain weighs about 3 pounds. In adults, the typical brain mass is roughly 1.3–1.4 kilograms, which converts to about 2.9–3.1 pounds, commonly rounded to 3 pounds. That’s the standard estimate most people memorize. The other values are noticeably off for an average adult brain: 2 pounds is lighter than the usual range, while 4 or 5 pounds would be heavier than what most adult brains weigh. Remember that there is some individual variation, but 3 pounds is the go-to approximation.