Brain size varies widely, depending largely on age, sex, and overall body mass. However, studies have suggested that the adult male brain weighs, on average, about 1,336 grams, whereas the adult female brain weighs around 1,198 grams.
In terms of dimensions, the human brain isn't the largest. Of all mammals, the sperm whale - an underwater denizen weighing an impressive 35-45 tons - is known to have the biggest brain.
But, of all the animals on Earth, human brains have the largest number of neurons, which are specialized cells that store and transmit information by electrical and chemical signals.
Traditionally, it has been said that the human brain contains approximately 100 billion neurons, but recent investigations have questioned the veracity of that number.
Instead, Brazilian neuroscientist Suzana Herculano-Houzel has discovered - by using a method that required liquefying donated human brains and turning them into a clear solution - that the number is closer to 86 billion neurons.