---
title: "Choice reaction time: 380 ms"
description: "Choice reaction time: typically 380 ms, really 300 ms to 500 ms. What is actually being measured, and why it counts as a reaction rather than one of the other two."
url: https://atoneplace.net/reaction-time/choice-reaction-time/
site: "At One Place"
---

# Choice reaction time

**Choice reaction time: 300 ms–500 ms**

Reaction — a decision, via the brain

Adding a decision costs roughly 100 to 150 milliseconds over simple reaction, and the cost grows with the number of alternatives in a way that is close to logarithmic — Hick's law, which says reaction time rises with the base-2 logarithm of the number of choices. That logarithm is why a menu of eight items is not four times slower than a menu of two, and it is one of the few laboratory findings that transfers cleanly into interface design.

## The numbers

- **Typical:** 380 ms
- **Range:** 300 ms to 500 ms
- **What it is:** Reaction — a decision, via the brain
- **What is measured:** Two or more stimuli, each with its own response. Press left for a red light, right for a green one.

## Why this is a reaction

A reaction is a decision: signal in, processing, movement out. The floor for a human is around 150 milliseconds, and anything measured below about 100 ms is anticipation rather than response.

## Where it sits against everything else

*Reflexes at the top, reactions in the middle, design values off the end of the scale.*

- Vestibulo-ocular reflex — Reflex: 10 ms
- Knee-jerk (patellar) reflex — Reflex: 22 ms
- Latency added by your screen and mouse — Physical limit: 35 ms
- Blink reflex — Reflex: 40 ms
- Withdrawal reflex — Reflex: 90 ms
- Time a jab takes to land — Physical limit: 110 ms
- Sprint start reaction — Reaction: 140 ms
- Simple tactile reaction time — Reaction: 155 ms
- Simple auditory reaction time — Reaction: 170 ms
- Professional gamer reaction time — Reaction: 190 ms
- Formula One start reaction — Reaction: 200 ms
- Simple visual reaction time — Reaction: 250 ms
- How reaction time changes with age — Reaction: 250 ms
- What sleep loss does to reaction time — Reaction: 300 ms
- What alcohol does to reaction time — Reaction: 320 ms
- Recognition reaction time — Reaction: 340 ms
- Choice reaction time — Reaction: 380 ms
- Time to hit a 95 mph fastball — Physical limit: 400 ms
- Time a goalkeeper has on a penalty — Physical limit: 450 ms
- Time to play a 90 mph delivery — Physical limit: 500 ms
- Driver reaction to an expected event — Reaction: 850 ms

## The basic senses

| What | Typical | Range | Kind |
| --- | --- | --- | --- |
| Simple tactile reaction time | 155 ms | 130 ms–190 ms | Reaction |
| Simple auditory reaction time | 170 ms | 140 ms–200 ms | Reaction |
| Simple visual reaction time | 250 ms | 200 ms–300 ms | Reaction |
| Recognition reaction time | 340 ms | 280 ms–450 ms | Reaction |

## Common questions

### How long is choice reaction time?

Typically 380 ms, with a real range of 300 ms to 500 ms. Two or more stimuli, each with its own response. Press left for a red light, right for a green one.

### Is that a reflex or a reaction?

Reaction — a decision, via the brain. A reaction is a decision: signal in, processing, movement out. The floor for a human is around 150 milliseconds, and anything measured below about 100 ms is anticipation rather than response.

## Related pages

- [Simple tactile reaction time](https://atoneplace.net/reaction-time/tactile-reaction-time/)
- [Simple auditory reaction time](https://atoneplace.net/reaction-time/auditory-reaction-time/)
- [Simple visual reaction time](https://atoneplace.net/reaction-time/visual-reaction-time/)
- [Recognition reaction time](https://atoneplace.net/reaction-time/recognition-reaction-time/)
- [A reflex is not a reaction](https://atoneplace.net/reaction-time/reflex-vs-reaction/)
- [Stopping distance at every speed](https://atoneplace.net/reaction-time/stopping-distance/)
- [Measure your own reaction time](https://atoneplace.net/tools/reaction-time-test/)

## Sources

- Response Times: Their Role in Inferring Elementary Mental Organization — R. Duncan Luce, Oxford University Press, 1986 (https://global.oup.com/academic/product/response-times-9780195036428)