GITNUXREPORT 2026

Brain Statistics

The human brain is a compact yet complex organ packed with billions of neurons.

Min-ji Park

Research Analyst focused on sustainability and consumer trends.

First published: Feb 13, 2026

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Statistic 1

The average adult human brain weighs about 1,300 to 1,400 grams, roughly 2% of total body weight.

Statistic 2

The cerebral cortex, the outer layer of the brain, has a surface area of about 2,500 square centimeters when unfolded.

Statistic 3

The human brain is composed of approximately 73-83% water by weight.

Statistic 4

The brainstem, which connects the brain to the spinal cord, measures about 7-8 cm in length.

Statistic 5

The frontal lobe occupies about 35% of the total cerebral cortex volume.

Statistic 6

The human brain contains around 1,000-2,000 km of blood vessels.

Statistic 7

The thickness of the cerebral cortex averages 2.5 mm, ranging from 1-4.5 mm across regions.

Statistic 8

The occipital lobe, responsible for vision, comprises about 18% of the neocortex.

Statistic 9

The brain's gray matter makes up 40% of its volume, white matter 60%.

Statistic 10

The corpus callosum, connecting hemispheres, is about 10 cm long and contains over 200 million axons.

Statistic 11

The average brain volume is 1,134 cm³ in women and 1,260 cm³ in men.

Statistic 12

The pineal gland weighs about 0.1 grams and is 5-8 mm in size.

Statistic 13

The hypothalamus weighs around 4 grams and regulates homeostasis.

Statistic 14

The cerebellum accounts for 10% of brain volume but 50% of neurons.

Statistic 15

The temporal lobe volume is approximately 15-20% of the cerebral hemispheres.

Statistic 16

The brain's meninges consist of three layers: dura, arachnoid, and pia mater.

Statistic 17

Ventricles hold about 25 ml of cerebrospinal fluid in adults.

Statistic 18

The falx cerebri divides the cerebral hemispheres longitudinally.

Statistic 19

The insula is buried within the lateral sulcus, measuring 5-7 cm deep.

Statistic 20

The brain stem includes midbrain (2 cm), pons (2.5 cm), and medulla (3 cm).

Statistic 21

The parietal lobe covers about 25% of the cortex surface.

Statistic 22

The amygdala is almond-shaped, about 1.5 cm long.

Statistic 23

The hippocampus volume averages 3-4 cm³ per side.

Statistic 24

The thalamus relays 99% of sensory information to cortex.

Statistic 25

The basal ganglia occupy 5-10% of brain volume.

Statistic 26

The sulci and gyri increase cortical surface area by 2-3 times.

Statistic 27

The human brain has 12 cranial nerves originating from it.

Statistic 28

The choroid plexus produces 500 ml of CSF daily.

Statistic 29

The limbic system includes structures totaling about 5% brain volume.

Statistic 30

The average adult brain length is 15-17 cm, width 14 cm, height 9 cm.

Statistic 31

The human brain contains approximately 86 billion neurons.

Statistic 32

Glial cells outnumber neurons by a ratio of about 1:1 in the human brain.

Statistic 33

There are roughly 85 billion neurons in the cerebral cortex alone.

Statistic 34

The cerebellum holds about 69 billion neurons, 80% of brain's total.

Statistic 35

Each cortical pyramidal neuron receives 7,000-10,000 synaptic inputs.

Statistic 36

The brain has over 100 trillion synapses in total.

Statistic 37

Astrocytes, a type of glia, number about 40-50 billion in the cortex.

Statistic 38

Oligodendrocytes produce myelin, insulating 10-50 axons each.

Statistic 39

Microglia constitute 10-15% of brain cells, acting as immune cells.

Statistic 40

Purkinje cells in cerebellum have up to 200,000 dendritic spines.

Statistic 41

Granule cells in cerebellum number 50 billion, smallest neurons.

Statistic 42

Synaptic vesicles per terminal: 100-1,000, releasing neurotransmitters.

Statistic 43

Neocortical neurons average 30 meters of dendrites per neuron.

Statistic 44

The brain produces 100 billion new synapses during early development.

Statistic 45

Ependymal cells line ventricles, numbering in millions.

Statistic 46

Schwann cells myelinate peripheral axons, absent in CNS.

Statistic 47

Basket cells inhibit Purkinje cells via 1-2 synapses each.

Statistic 48

Neurons fire action potentials at 1-100 Hz rates typically.

Statistic 49

GABAergic interneurons comprise 20% of cortical neurons.

Statistic 50

Dopaminergic neurons in substantia nigra: about 400,000.

Statistic 51

Serotonergic neurons in raphe nuclei: around 250,000.

Statistic 52

Cholinergic neurons in basal forebrain: 100,000-200,000.

Statistic 53

Axons can extend up to 1 meter in length in the brain.

Statistic 54

The fetal brain forms 250,000 neurons per minute during peak.

Statistic 55

Synaptogenesis peaks at 1 quadrillion synapses by age 3.

Statistic 56

Brain volume triples from birth to age 3, reaching 80% adult size.

Statistic 57

Myelination completes 90% by age 3, full by 25 years.

Statistic 58

Critical period for language ends around age 7-12.

Statistic 59

Prefrontal cortex thins 1% per year from adolescence to 30.

Statistic 60

Hippocampus volume increases 20% from childhood to adulthood.

Statistic 61

Infant brain uses 65% of resting energy at birth, drops to 43% by age 5.

Statistic 62

Synapse pruning eliminates 50% excess by adolescence.

Statistic 63

Visual cortex sensitive period: birth to 8 years.

Statistic 64

Brain lateralization completes by age 10 for most functions.

Statistic 65

Adolescent brain reward sensitivity peaks at 15, risk-taking high.

Statistic 66

Adult neurogenesis rate: 1,400 new hippocampal neurons daily.

Statistic 67

Cortical gray matter peaks at 11-12 years, then declines.

Statistic 68

Sleep needs drop from 16 hours newborn to 10 hours age 5.

Statistic 69

Mirror neuron system develops by 12 months for imitation.

Statistic 70

Thalamic inputs wire cortex in first 6 months post-birth.

Statistic 71

Brainstem reflexes mature by 3-6 months.

Statistic 72

Executive function improves 300% from age 3 to adulthood.

Statistic 73

Cerebellum grows 5x volume in first year.

Statistic 74

Attachment shapes amygdala by age 2.

Statistic 75

Brain entropy peaks at age 10, stabilizes later.

Statistic 76

Pubertal hormones remodel 10% prefrontal connections.

Statistic 77

Lifespan brain shrinkage: 5 ml/year after 40.

Statistic 78

Alzheimer's affects 10% over 65, 33% over 85.

Statistic 79

Stroke incidence: 795,000 cases/year in US, brain damage primary.

Statistic 80

Parkinson's disease: 1% population over 60, dopamine neurons lost 50-80%.

Statistic 81

Epilepsy: 50 million worldwide, 1 in 26 lifetime risk.

Statistic 82

Brain tumors: 23/100,000 incidence, gliomas 30% malignant.

Statistic 83

Traumatic brain injury: 69 million global/year, 50% severe cognitive impact.

Statistic 84

Multiple sclerosis: 2.8 million worldwide, demyelination key.

Statistic 85

Depression: 280 million affected, shrinks hippocampus 10-15%.

Statistic 86

Schizophrenia: 1% lifetime risk, dopamine hypothesis central.

Statistic 87

Migraine: 15% population, cortical spreading depression trigger.

Statistic 88

Autism spectrum: 1 in 54 children, brain overgrowth early.

Statistic 89

ADHD: 5-7% children, prefrontal hypoactivity.

Statistic 90

ALS: 2/100,000 incidence, motor neurons degenerate 100%.

Statistic 91

Huntington's: 5-10/100,000, striatal neuron loss progressive.

Statistic 92

Brain aneurysm rupture: 10% mortality, 50,000 US/year.

Statistic 93

Encephalitis: 10-15/100,000/year viral, inflammation widespread.

Statistic 94

Meningitis bacterial: 1.2 million cases/year global, 20% fatality.

Statistic 95

Prion diseases like CJD: 1/million/year, 100% fatal rapid.

Statistic 96

Glioblastoma: median survival 15 months post-diagnosis.

Statistic 97

Concussion recovery: 80% within 7-10 days, chronic 10-20%.

Statistic 98

Hydrocephalus: 1/1,000 births, ventricle enlargement.

Statistic 99

Narcolepsy: 50/100,000, orexin neurons 90% lost.

Statistic 100

Frontotemporal dementia: 15-22/100,000 over 45.

Statistic 101

Wernicke-Korsakoff: thiamine deficiency, 1-2% alcoholics.

Statistic 102

Creutzfeldt-Jakob disease incubation 10-40 years prions.

Statistic 103

Brain abscess: 2,000-3,000 US/year, 10-20% mortality.

Statistic 104

The brain uses 20% of body's oxygen despite 2% mass.

Statistic 105

Neurons transmit signals at speeds up to 120 m/s in myelinated axons.

Statistic 106

Short-term memory holds 7 ± 2 items for 20-30 seconds.

Statistic 107

The brain processes visual information 60,000 times faster than text.

Statistic 108

Hippocampus can store about 2.5 petabytes of memories over lifetime.

Statistic 109

Brain consumes 20-25 watts of power continuously.

Statistic 110

Reaction time to visual stimulus averages 250 ms.

Statistic 111

The fovea processes 50% of visual cortex activity despite 1% retina.

Statistic 112

Working memory capacity peaks at 4±1 chunks in adults.

Statistic 113

Brain waves in alpha state: 8-12 Hz during relaxation.

Statistic 114

Language areas (Broca/Wernicke) activate in 200-400 ms for speech.

Statistic 115

Mirror neurons fire both during action and observation.

Statistic 116

Default mode network active during mind-wandering, 60-80% wake time.

Statistic 117

Brain plasticity allows 1-10% synapse strengthening per LTP event.

Statistic 118

Olfactory bulb processes 10,000 odors distinguishable.

Statistic 119

Pain signals processed in 100-200 ms via spinothalamic tract.

Statistic 120

REM sleep occupies 20-25% of total sleep time in adults.

Statistic 121

Brain's reward system releases 10x dopamine on drugs vs. food.

Statistic 122

Spatial navigation uses 1% of cortex for grid cells.

Statistic 123

Emotional memory recall 2-3x stronger than neutral.

Statistic 124

Auditory cortex processes 40 Hz gamma for speech rhythm.

Statistic 125

Motor cortex maps body with homunculus, hand 30% area.

Statistic 126

Consciousness correlates with 40 Hz gamma synchrony.

Statistic 127

Brain filters 99% of sensory input subconsciously.

Statistic 128

Episodic memory degrades 20% per decade after 30.

Statistic 129

Prefrontal cortex matures at 25, enabling impulse control.

Statistic 130

Brain solves insight problems via right hemisphere alpha waves.

Statistic 131

Neurogenesis adds 700 new neurons daily in adult hippocampus.

1/131

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While it may only weigh about three pounds, your brain is a universe of staggering statistics, from its 86 billion neurons firing within a cortex thinner than a coin to a network of blood vessels long enough to stretch across a country.

Key Takeaways

The average adult human brain weighs about 1,300 to 1,400 grams, roughly 2% of total body weight.
The cerebral cortex, the outer layer of the brain, has a surface area of about 2,500 square centimeters when unfolded.
The human brain is composed of approximately 73-83% water by weight.
The human brain contains approximately 86 billion neurons.
Glial cells outnumber neurons by a ratio of about 1:1 in the human brain.
There are roughly 85 billion neurons in the cerebral cortex alone.
The brain uses 20% of body's oxygen despite 2% mass.
Neurons transmit signals at speeds up to 120 m/s in myelinated axons.
Short-term memory holds 7 ± 2 items for 20-30 seconds.
The fetal brain forms 250,000 neurons per minute during peak.
Synaptogenesis peaks at 1 quadrillion synapses by age 3.
Brain volume triples from birth to age 3, reaching 80% adult size.
Alzheimer's affects 10% over 65, 33% over 85.
Stroke incidence: 795,000 cases/year in US, brain damage primary.
Parkinson's disease: 1% population over 60, dopamine neurons lost 50-80%.

The human brain is a compact yet complex organ packed with billions of neurons.

Anatomy

The average adult human brain weighs about 1,300 to 1,400 grams, roughly 2% of total body weight.
The cerebral cortex, the outer layer of the brain, has a surface area of about 2,500 square centimeters when unfolded.
The human brain is composed of approximately 73-83% water by weight.
The brainstem, which connects the brain to the spinal cord, measures about 7-8 cm in length.
The frontal lobe occupies about 35% of the total cerebral cortex volume.
The human brain contains around 1,000-2,000 km of blood vessels.
The thickness of the cerebral cortex averages 2.5 mm, ranging from 1-4.5 mm across regions.
The occipital lobe, responsible for vision, comprises about 18% of the neocortex.
The brain's gray matter makes up 40% of its volume, white matter 60%.
The corpus callosum, connecting hemispheres, is about 10 cm long and contains over 200 million axons.
The average brain volume is 1,134 cm³ in women and 1,260 cm³ in men.
The pineal gland weighs about 0.1 grams and is 5-8 mm in size.
The hypothalamus weighs around 4 grams and regulates homeostasis.
The cerebellum accounts for 10% of brain volume but 50% of neurons.
The temporal lobe volume is approximately 15-20% of the cerebral hemispheres.
The brain's meninges consist of three layers: dura, arachnoid, and pia mater.
Ventricles hold about 25 ml of cerebrospinal fluid in adults.
The falx cerebri divides the cerebral hemispheres longitudinally.
The insula is buried within the lateral sulcus, measuring 5-7 cm deep.
The brain stem includes midbrain (2 cm), pons (2.5 cm), and medulla (3 cm).
The parietal lobe covers about 25% of the cortex surface.
The amygdala is almond-shaped, about 1.5 cm long.
The hippocampus volume averages 3-4 cm³ per side.
The thalamus relays 99% of sensory information to cortex.
The basal ganglia occupy 5-10% of brain volume.
The sulci and gyri increase cortical surface area by 2-3 times.
The human brain has 12 cranial nerves originating from it.
The choroid plexus produces 500 ml of CSF daily.
The limbic system includes structures totaling about 5% brain volume.
The average adult brain length is 15-17 cm, width 14 cm, height 9 cm.

Anatomy Interpretation

While it's roughly the size of a small cauliflower and nearly as wet, your three-pound universe of folded gray matter is a master of deceptive packaging, cramming a city's worth of blood vessels and a hundred billion neurons into a space where a 10-centimeter bridge handles more traffic than the world's busiest commuter lane.

Cellular Composition

The human brain contains approximately 86 billion neurons.
Glial cells outnumber neurons by a ratio of about 1:1 in the human brain.
There are roughly 85 billion neurons in the cerebral cortex alone.
The cerebellum holds about 69 billion neurons, 80% of brain's total.
Each cortical pyramidal neuron receives 7,000-10,000 synaptic inputs.
The brain has over 100 trillion synapses in total.
Astrocytes, a type of glia, number about 40-50 billion in the cortex.
Oligodendrocytes produce myelin, insulating 10-50 axons each.
Microglia constitute 10-15% of brain cells, acting as immune cells.
Purkinje cells in cerebellum have up to 200,000 dendritic spines.
Granule cells in cerebellum number 50 billion, smallest neurons.
Synaptic vesicles per terminal: 100-1,000, releasing neurotransmitters.
Neocortical neurons average 30 meters of dendrites per neuron.
The brain produces 100 billion new synapses during early development.
Ependymal cells line ventricles, numbering in millions.
Schwann cells myelinate peripheral axons, absent in CNS.
Basket cells inhibit Purkinje cells via 1-2 synapses each.
Neurons fire action potentials at 1-100 Hz rates typically.
GABAergic interneurons comprise 20% of cortical neurons.
Dopaminergic neurons in substantia nigra: about 400,000.
Serotonergic neurons in raphe nuclei: around 250,000.
Cholinergic neurons in basal forebrain: 100,000-200,000.
Axons can extend up to 1 meter in length in the brain.

Cellular Composition Interpretation

In this dense symphony of roughly 86 billion neural soloists, a vast supporting cast of glial stagehands not only outnumbers them but diligently ensures that each player—from the cerebellum's 69-billion-strong choir to the cortex's intricately wired virtuosos—can perform its staggering 100-trillion synaptic conversations with precision, making our every thought a logistical marvel on a cellular scale.

Development

The fetal brain forms 250,000 neurons per minute during peak.
Synaptogenesis peaks at 1 quadrillion synapses by age 3.
Brain volume triples from birth to age 3, reaching 80% adult size.
Myelination completes 90% by age 3, full by 25 years.
Critical period for language ends around age 7-12.
Prefrontal cortex thins 1% per year from adolescence to 30.
Hippocampus volume increases 20% from childhood to adulthood.
Infant brain uses 65% of resting energy at birth, drops to 43% by age 5.
Synapse pruning eliminates 50% excess by adolescence.
Visual cortex sensitive period: birth to 8 years.
Brain lateralization completes by age 10 for most functions.
Adolescent brain reward sensitivity peaks at 15, risk-taking high.
Adult neurogenesis rate: 1,400 new hippocampal neurons daily.
Cortical gray matter peaks at 11-12 years, then declines.
Sleep needs drop from 16 hours newborn to 10 hours age 5.
Mirror neuron system develops by 12 months for imitation.
Thalamic inputs wire cortex in first 6 months post-birth.
Brainstem reflexes mature by 3-6 months.
Executive function improves 300% from age 3 to adulthood.
Cerebellum grows 5x volume in first year.
Attachment shapes amygdala by age 2.
Brain entropy peaks at age 10, stabilizes later.
Pubertal hormones remodel 10% prefrontal connections.
Lifespan brain shrinkage: 5 ml/year after 40.

Development Interpretation

It seems our brain spends its first few years in a furious startup phase, peaks as a dramatic teenage saga, and then spends adulthood calmly downsizing and remodeling.

Diseases

Alzheimer's affects 10% over 65, 33% over 85.
Stroke incidence: 795,000 cases/year in US, brain damage primary.
Parkinson's disease: 1% population over 60, dopamine neurons lost 50-80%.
Epilepsy: 50 million worldwide, 1 in 26 lifetime risk.
Brain tumors: 23/100,000 incidence, gliomas 30% malignant.
Traumatic brain injury: 69 million global/year, 50% severe cognitive impact.
Multiple sclerosis: 2.8 million worldwide, demyelination key.
Depression: 280 million affected, shrinks hippocampus 10-15%.
Schizophrenia: 1% lifetime risk, dopamine hypothesis central.
Migraine: 15% population, cortical spreading depression trigger.
Autism spectrum: 1 in 54 children, brain overgrowth early.
ADHD: 5-7% children, prefrontal hypoactivity.
ALS: 2/100,000 incidence, motor neurons degenerate 100%.
Huntington's: 5-10/100,000, striatal neuron loss progressive.
Brain aneurysm rupture: 10% mortality, 50,000 US/year.
Encephalitis: 10-15/100,000/year viral, inflammation widespread.
Meningitis bacterial: 1.2 million cases/year global, 20% fatality.
Prion diseases like CJD: 1/million/year, 100% fatal rapid.
Glioblastoma: median survival 15 months post-diagnosis.
Concussion recovery: 80% within 7-10 days, chronic 10-20%.
Hydrocephalus: 1/1,000 births, ventricle enlargement.
Narcolepsy: 50/100,000, orexin neurons 90% lost.
Frontotemporal dementia: 15-22/100,000 over 45.
Wernicke-Korsakoff: thiamine deficiency, 1-2% alcoholics.
Creutzfeldt-Jakob disease incubation 10-40 years prions.
Brain abscess: 2,000-3,000 US/year, 10-20% mortality.

Diseases Interpretation

While our brains grant us consciousness and creativity, they are also heartbreakingly vulnerable, facing a relentless statistical siege from diseases that chip away at everything from memory and movement to our very sense of self.

Functions

The brain uses 20% of body's oxygen despite 2% mass.
Neurons transmit signals at speeds up to 120 m/s in myelinated axons.
Short-term memory holds 7 ± 2 items for 20-30 seconds.
The brain processes visual information 60,000 times faster than text.
Hippocampus can store about 2.5 petabytes of memories over lifetime.
Brain consumes 20-25 watts of power continuously.
Reaction time to visual stimulus averages 250 ms.
The fovea processes 50% of visual cortex activity despite 1% retina.
Working memory capacity peaks at 4±1 chunks in adults.
Brain waves in alpha state: 8-12 Hz during relaxation.
Language areas (Broca/Wernicke) activate in 200-400 ms for speech.
Mirror neurons fire both during action and observation.
Default mode network active during mind-wandering, 60-80% wake time.
Brain plasticity allows 1-10% synapse strengthening per LTP event.
Olfactory bulb processes 10,000 odors distinguishable.
Pain signals processed in 100-200 ms via spinothalamic tract.
REM sleep occupies 20-25% of total sleep time in adults.
Brain's reward system releases 10x dopamine on drugs vs. food.
Spatial navigation uses 1% of cortex for grid cells.
Emotional memory recall 2-3x stronger than neutral.
Auditory cortex processes 40 Hz gamma for speech rhythm.
Motor cortex maps body with homunculus, hand 30% area.
Consciousness correlates with 40 Hz gamma synchrony.
Brain filters 99% of sensory input subconsciously.
Episodic memory degrades 20% per decade after 30.
Prefrontal cortex matures at 25, enabling impulse control.
Brain solves insight problems via right hemisphere alpha waves.
Neurogenesis adds 700 new neurons daily in adult hippocampus.

Functions Interpretation

Our brain is a wildly overclocked, energy-hungry supercomputer that brilliantly filters out almost everything we experience so that, with a power draw barely enough to dim a bulb, we can hold onto the most vivid emotional memories while constantly daydreaming and sometimes accidentally solving complex problems in our sleep.

Sources & References

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