Multiple choice general knowledge science & technology Your brain can weigh between two and three pounds by the time you are an adult. True False Reveal answer Fill a bubble to check yourself A Correct answer Explanation The adult human brain typically weighs between 2-3 pounds (approximately 1.3-1.4 kg on average). This weight remains relatively consistent across adults, making up about 2% of body weight while consuming about 20% of the body's energy.