Reaction Time by Age
Reaction time peaks in your late teens and slowly declines. Here is the full breakdown by age group, what causes the decline, and why some 60-year-olds still outperform 30-year-olds.
How reaction time changes with age
Reaction time follows a predictable arc across the human lifespan. Young children are slow because their nervous systems are still developing. Speed climbs through childhood and adolescence, peaks in the late teens, holds roughly flat through the twenties, and then starts a long, slow decline that accelerates after 60. The shape of the curve is remarkably consistent across studies — what varies is the exact peak age and the rate of decline, both of which depend on lifestyle.
The peak is around 17 to 19 years old. By that age, the nervous system is fully myelinated (the fatty insulation around nerve fibres that speeds signal conduction), dopamine systems are at maximum activity, and synaptic density is at its adult-set level. Teenagers in this band routinely post simple visual RT scores of 195–235 ms, the fastest of any age group.
After about age 25, reaction time slows by roughly 1–2 milliseconds per year. By age 50 most adults have lost 25–30 ms relative to their teenage peak. By age 70 the gap is closer to 70 ms. These are averages, though — the spread widens dramatically with age. Physically active seniors often match sedentary 30-year-olds, while inactive seniors slow much more sharply. Lifestyle matters more than chronological age.
Average reaction time by age group
Click any age group for the full breakdown, including what causes the scores, training implications, and how to interpret your own result.
| Age range | Average | Fast (top 5%) | Slow (bottom 5%) |
|---|---|---|---|
| Ages 6–9 | 290 ms | 240 ms | 360 ms |
| Ages 10–13 | 260 ms | 215 ms | 320 ms |
| Ages 14–19 | 235 ms | 195 ms | 290 ms |
| Ages 20–29 | 245 ms | 200 ms | 305 ms |
| Ages 30–39 | 255 ms | 210 ms | 320 ms |
| Ages 40–49 | 270 ms | 225 ms | 340 ms |
| Ages 50–59 | 290 ms | 245 ms | 365 ms |
| Ages 60–69 | 315 ms | 265 ms | 400 ms |
| Ages 70+ | 355 ms | 300 ms | 460 ms |
Why teenagers are the fastest humans
The teenage peak is not a coincidence. Three biological factors converge in late adolescence to produce the fastest reaction times of any age group.
Myelination. The myelin sheath around nerve fibres acts like insulation on a wire — it speeds signal conduction. The last parts of the brain to fully myelinate are the frontal lobes, which finish around age 25. But the motor and sensory pathways that matter for reaction time are fully myelinated by about age 17, which is when speed peaks.
Dopamine. Dopamine is the neurotransmitter that drives reward-seeking behaviour, motor initiation, and decision speed. Dopamine receptor density peaks in late adolescence and then slowly declines. Lower dopamine means slower motor initiation — which is one reason why older adults are slower on RT tests even when their nerve conduction speed is fine.
Synaptic plasticity. The teenage brain has more synapses than the adult brain, and those synapses are more plastic. That means faster learning and faster adaptation, both of which translate into faster responses on novel tasks. As we age, synaptic pruning removes unused connections, which makes the brain more efficient but less adaptable.
Why the decline is slower than you think
People tend to overestimate how much reaction time slows with age. The popular image is that once you hit 40, your reflexes are gone — but the data tells a different story. A healthy 45-year-old is typically only 15–20 ms slower than they were at 20. That is the difference between a 240 ms and a 260 ms score. Noticeable on a test, invisible in real life.
The decline accelerates after 60, but even then the spread is enormous. The Baltimore Longitudinal Study of Aging tracked simple RT across more than 2,000 adults over 30 years. At age 70, the median RT was 315 ms — but the fittest quartile was still under 280 ms, matching the typical 35-year-old. Cardio fitness, sleep quality, and continued cognitive challenge all blunt the decline.
The takeaway: age is a real factor, but it is not destiny. If you want to keep your reflexes sharp into your 60s and 70s, the evidence-based interventions are cardio exercise, action video games (or other fast-paced visual activities), good sleep, and learning new skills. None of these will make you faster than a teenager, but they will keep you closer to your younger self than the averages suggest.