The ten animals with the most neurons in the whole brain, among species with published counts or estimates, from the African elephant (257 billion) to the rhesus macaque (6.376 billion).
The African Elephant has the most neurons of any animal with a published count, about 257 billion in the whole brain. Humans are second at about 86 billion and the common minke whale third at about 57.4 billion. The ranking uses whole-brain neuron numbers compiled on Wikipedia from Herculano-Houzel and colleagues, plus a 2025 minke whale count, as of October 2026.
Neurons are the information-processing cells of the nervous system, and how many a brain holds is one rough gauge of its processing capacity. The African elephant tops the list at about 257 billion, three times the human count, but 97.5% of those neurons are in the cerebellum. Humans have the most neurons in the cerebral cortex of any species counted with the same method. This list ranks animals by total neurons in the whole brain. Most figures are direct counts made with the isotropic fractionator method developed by Suzana Herculano-Houzel. The three great-ape figures are estimates from scaling rules and are labelled as such. Only a small share of species has been counted, so this is a ranking of the animals measured so far, not of every animal alive.
The African elephant brain holds about 257 billion neurons, three times the human total. About 251 billion of them (97.5%) sit in the cerebellum; the cerebral cortex has only about 5.6 billion, roughly a third of the human figure.
The average adult human brain holds about 86 billion neurons: about 16 billion in the cerebral cortex and about 69 billion in the cerebellum. That 16 billion is the highest cortical count measured with the same counting method in any species.
A 2025 isotropic-fractionator count of one northern minke whale brain found about 57.4 billion neurons, about 54.2 billion of them in the cerebellum. Its cerebral cortex held only about 3.1 to 3.2 billion, far below older stereology estimates for the species.
The gorilla figure of about 33.4 billion neurons is an estimate, not a whole-brain count: researchers counted cells in the cerebellum and applied primate scaling rules to the brain's size. A gorilla brain is roughly a third the size of a human brain, though the animal is larger.
The orangutan's roughly 32.6 billion neurons is, like the gorilla's, an estimate from primate scaling rules and partial cell counts rather than a full count of the brain.
The chimpanzee's estimated 28 billion neurons comes from applying primate scaling rules to brain size, so it carries more uncertainty than the counted figures elsewhere on this list.
The yellow baboon brain holds about 10.95 billion neurons, the most among the monkeys that have been counted directly. About 2.9 billion of those are in the cerebral cortex.
The giraffe brain holds about 10.75 billion neurons, but only about 1.7 billion in the cerebral cortex, part of a pattern of large, folded cortices with relatively few neurons found across even-toed hoofed mammals.
The brown bear brain holds about 9.59 billion neurons, yet only about 0.25 billion in its cerebral cortex, a small fraction of its total.
The rhesus macaque brain holds about 6.38 billion neurons, about 1.7 billion of them in the cerebral cortex. It is one of the most widely studied primates in neuroscience.
| # | Name | Scientific name | Count basis | Cortical neurons | Study |
|---|---|---|---|---|---|
| 1 | African Elephant | Loxodonta africana | Counted (isotropic fractionator) | 5.6 billion | Herculano-Houzel et al. 2014 |
| 2 | Human | Homo sapiens | Counted (isotropic fractionator) | 16.3 billion | Azevedo et al. 2009 |
| 3 | Common Minke Whale | Balaenoptera acutorostrata | Counted (isotropic fractionator), one brain | 3.1 to 3.2 billion | Avelino-de-Souza et al. 2025 |
| 4 | Gorilla | Gorilla gorilla | Estimated from primate scaling rules | 9.1 billion (estimated) | Herculano-Houzel & Kaas 2011 |
| 5 | Orangutan | Pongo | Estimated from primate scaling rules | 7.7 to 8.9 billion (estimated) | Herculano-Houzel & Kaas 2011 |
| 6 | Chimpanzee | Pan troglodytes | Estimated from primate scaling rules | 7.4 billion (optical fractionator, one hemisphere) | Herculano-Houzel 2012 |
| 7 | Yellow Baboon | Papio cynocephalus | Counted (isotropic fractionator) | 2.88 billion | Gabi et al. 2010 |
| 8 | Giraffe | Giraffa camelopardalis | Counted (isotropic fractionator) | 1.73 billion | Kazu et al. 2014 |
| 9 | Brown Bear | Ursus arctos | Counted (isotropic fractionator) | 0.25 billion | Jardim-Messeder et al. 2017 |
| 10 | Rhesus Macaque | Macaca mulatta | Counted (isotropic fractionator) | 1.71 billion | Herculano-Houzel et al. 2007 |
Animals are ranked by total number of neurons in the whole brain (not the spinal cord or peripheral nerves), in billions. Figures come from the whole-nervous-system table of Wikipedia's List of animals by number of neurons (revision of 2 September 2026) and the peer-reviewed studies it cites, almost all by Herculano-Houzel and colleagues using the isotropic fractionator, which turns brain tissue into a countable suspension of cell nuclei. The common minke whale figure (57.4 billion) comes from the 2025 peer-reviewed isotropic-fractionator study of one northern minke whale. The gorilla, orangutan and chimpanzee figures are estimates from primate cellular scaling rules, not whole-brain counts; each entry's 'Count basis' says which kind of figure it is. Wikipedia's table also lists a short-finned pilot whale at 128 billion, sourced only to a thesis record; we could not find that figure in any peer-reviewed study, so it is excluded until it is published. Cortical neuron figures come from the same Wikipedia page's forebrain table.
Almost all of the difference is in the cerebellum, which holds about 251 billion of the elephant's 257 billion neurons. The elephant's cerebral cortex has about 5.6 billion neurons, roughly a third of the human figure of about 16 billion.
Most figures here come from the isotropic fractionator: brain tissue is dissolved into a uniform suspension of cell nuclei, and the neuronal nuclei are stained and counted in samples. The gorilla, orangutan and chimpanzee figures were not counted this way for the whole brain; they are estimates from scaling rules worked out in other primates.
Few cetacean brains have been counted whole. A 2025 isotropic-fractionator study of a common minke whale found about 57.4 billion neurons, which places it third here. Wikipedia also lists a short-finned pilot whale at 128 billion, but that figure traces only to a thesis record and no peer-reviewed source, so it is not ranked.
No. Total neuron count is only one factor. Researchers, including Herculano-Houzel, argue that the number of neurons in the cerebral cortex says more about cognitive capacity than the total, which is why humans rank first on cortical neurons despite ranking second here.
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