Animal reaction time: what the studies measured
What animal has the fastest reaction time? Among the reaction times we could verify, the shortest is the desert kangaroo rat's 18.8 ms, measured in the wild against a simulated rattlesnake strike.1 That is a measurement of those animals in that setup, not a ranking of all animals. People who search for the fastest reaction time animal expect one winner, but the sources do not give one. A snake strike, an ant's jaw closing and a mantis shrimp's blow are movement times, not reaction times, so they are listed apart.
Three things people call fast
- Reaction time From a stimulus to the first movement in response. This is what the reaction time test measures in people.
- Movement time How long a strike, jump or jaw closing lasts once it has started. A snake strike duration is this.
- Speed How fast a body part travels, in meters per second. It says nothing about when the animal started to move.
How to read these animal numbers
- Lab and field differ. The snake strikes in the first study were defensive, aimed at a stuffed glove, at 27 °C. The rodent and rattlesnake figures are from wild animals at night.
- A simulated stimulus is not a real one. The rodents faced a spring-driven cork moving at 2.8 m/s, about the speed of a rattlesnake strike. Wild kangaroo rats facing real rattlesnakes had a response time of 61.5 ms, much longer than the simulated-strike figures. The stimulus, the way it was measured and the trials kept all differ, so we do not treat either figure as the right one.4
- Samples are small. The wild rattlesnake data are 4 captures and 4 misses. The rodent figures leave out trials where the animal was hit before it reacted.
- Some sources were read in the abstract only. The mantis shrimp, spearing mantis shrimp and fruit fly figures say no more than their abstracts do.
- Left out on purpose. We found no verified speed for the peacock mantis shrimp, no housefly figure and no general cat figure, so none is given.
Animal reaction time FAQ
What animal has the fastest reaction time?
No study we read ranks animals, so there is no single answer. Among the reaction times we could verify, the shortest is the desert kangaroo rat's 18.8 ms, measured in the wild against a simulated rattlesnake strike. It is one measurement in one setup. Snake strikes, ant jaws and mantis shrimp blows are movement times, not reaction times, and are listed apart.
What animal has the fastest reflexes?
The sources we read do not rank animals by reflexes. They time different things: how soon an animal starts to move after a stimulus, how long a strike takes once it starts, and how fast a body part travels. The table says which is which. Among the reaction times listed, all six rodent species began to move within 18.8 to 36.8 ms of a simulated snake strike starting.
What is a cat's reaction time?
We did not find a standard cat reaction time in the sources we could read. A lab study of six trained cats found that reaction time to a tone fell as the tone got louder, and for one example cat the fitted value was 466 ms at 20 dB SPL, near its hearing threshold. A second study found that cats responded more slowly as visual contrast fell. Neither is a general figure for how fast a cat reacts.
Cat vs snake reaction time: which is faster?
We found no source that times a cat against a snake, so this page makes no claim about which animal has the fastest reaction time. What is sourced: a defensive snake strike took 48 to 84 ms from start to contact in one lab study, and kangaroo rats and other rodents began to move 18.8 to 36.8 ms after a simulated strike started. The only cat figure we have is for a tone near the hearing threshold, which is a different task.
How fast are cats reflexes?
We found no general figure for it. The sourced results are narrower: in a lab study of six trained cats, reaction time to a tone fell as the tone got louder, with a fitted value of 466 ms for one example cat near its hearing threshold, and a second study found slower visual responses as contrast fell. Neither tells you how fast a cat reacts to something it sees move.
Is a snake strike a reaction time?
No. A strike duration is how long the strike lasts once the snake has started it, measured from the start of the strike to contact. A reaction time starts at a stimulus and ends at the first response. The two are listed in separate tables on this page for that reason.
How does human reaction time compare with animals?
A group of 1,469 adults aged 18 to 65 had a mean simple visual reaction time of 231 ms (213 ms after removing the measured hardware delay), pressing a mouse button on a 60 Hz screen. The rodent figures end at the first visible movement, not at a finished button press, and the stimulus differs, so the two cannot be read as a like-for-like ranking. You can measure yours with the reaction time test.
Reaction times: from a stimulus to the first movement
Six wild, nocturnal rodent species were tested in the field, each animal once, with a simulated rattlesnake strike: a compressed spring that projects a cork toward the animal at 2.8 m/s. Reaction time is the time from the first movement of the cork to the first visible movement of the animal. The study also reports take-off time.1
| Species | Animals | Reaction time (ms) | Take-off time (ms) |
|---|---|---|---|
| Merriam's kangaroo rat | 39 | 22.8 ± 1.2 | 103.1 ± 8.3 |
| Desert kangaroo rat | 24 | 18.8 ± 1.5 | 77.8 ± 6.0 |
| Banner-tailed kangaroo rat | 24 | 29.4 ± 1.4 | 101.9 ± 13.5 |
| Desert pocket mouse | 21 | 28.4 ± 2.2 | 58.2 ± 10.5 |
| White-throated woodrat | 13 | 19.1 ± 1.0 | 152.5 ± 12.3 |
| California ground squirrel | 21 | 36.8 ± 2.1 | 157.7 ± 12.2 |
Mean ± standard error. Trials were left out when the animal was hit by the cork before it reacted (20 trials) or seemed to react before the cork moved (2 trials).
| Animal | What was timed | Value | Source |
|---|---|---|---|
| Wild kangaroo rat, real rattlesnake | Response time to a real strike, stationary rats only. The two rats that evaded the strike took 24 ms and 30 ms from the start of the escape to clearing the strike path. | 61.5 ± 10.6 ms | 4 |
| Trained cat | Reaction time to a 1 kHz tone at 20 dB SPL, from a fitted curve, for one example cat out of six. Louder tones gave shorter times. | 466 ms | 3 |
| Human, for comparison | Mean simple visual reaction time of 1,469 adults aged 18 to 65, pressing a mouse button on a 60 Hz screen. 213 ms after removing the measured hardware delay. | 231 ms | 5 |
Strike and jaw times: not reaction time
These are movement times and speeds. They tell you how fast a strike is once it has begun, and nothing about how soon the animal began it. Animal reaction time and strike time are different quantities, so do not read one against the other.
| Animal | What was timed | Value | Source |
|---|---|---|---|
| Texas ratsnake, western cottonmouth, western diamond-backed rattlesnake | Defensive strike duration, from the start of the strike to first contact, mean ± s.e.m.: ratsnake 74 ± 2 ms, cottonmouth 66 ± 5 ms, rattlesnake 71 ± 2 ms. 14 ratsnakes, 6 cottonmouths and 12 rattlesnakes, a stuffed glove as the target, filmed at 250 Hz. | 48 to 84 ms across all snakes | 2 |
| Mohave rattlesnake, wild | Time from the start of a strike to capture of a kangaroo rat, at night, 4 captures, filmed at 500 frames per second. | 105 ms mean, range 48 to 170 ms | 4 |
| Trap-jaw ant, Odontomachus bauri | Time for the mandibles to close, filmed at 50,000 frames per second. Closing speed averaged 38.4 m/s. | 0.13 ms (SD 0.05), shortest 0.06 ms | 6 |
| Smashing mantis shrimp, Gonodactylus smithii | Speed of the strike, a speed and not a time. | 30 m/s | 7 |
| Spearing mantis shrimp, two species | Strike duration of Alachosquilla vicina and of Lysiosquillina maculata. Spearers strike far slower than smashers. | 3.26 ms and 24.98 ms | 8 |
| Peacock mantis shrimp | Described as an extremely fast, spring-loaded strike. We could not verify a speed figure, so none is given. | Not given | 9 |
| Fruit fly, Drosophila | Lead time: flies begin adjusting their posture about this long before takeoff when escaping a looming object. Not a stimulus-to-movement reaction time, and not the housefly. | About 200 ms | 10 |
One result surprises people: in the same study the ratsnake, a harmless snake, matched or exceeded the vipers in strike performance.2
Cat reaction time
We did not find a standard cat reaction time in the sources we could read, so this page gives none. What exists is lab work on trained cats, and it shows that reaction time depends on the stimulus.
In a study of six cats trained to respond to tones, median reaction time fell as the tone got louder. For one example cat the fitted value was 466 ms at 20 dB SPL for a 1 kHz tone, near its hearing threshold. The authors describe some cats as slow and some as rapid.3 That is one trained animal responding to a faint sound. It does not describe how fast a cat reacts to something it sees move.
A second lab study found that at every spatial frequency tested, a cat's visual reaction time increased as the contrast of the pattern fell. The abstract gives the direction, not milliseconds.11
Cat vs snake reaction time
We found no source that times a cat against a snake, so we do not say which is faster. The sourced snake figure is a strike duration of 48 to 84 ms. That is a movement time, and it is not comparable to a cat's tone-detection time. The only reaction times we have for animals facing a snake strike are for rodents, in the table above.
How you compare
The human figure in the table is one study: 1,469 adults aged 18 to 65 had a mean simple visual reaction time of 231 ms, or 213 ms after removing the hardware delay the authors measured, pressing a mouse button on a 60 Hz screen.5 Your own number comes from the reaction time test above, which is you plus your screen, input device and browser.
Do not line it up against the rodent figures. A human reaction time here ends at a registered button press, after the hand has moved, and the signal is a color change on a screen. The rodent figures end at the first visible movement of any kind, and the signal is a moving object. The published human figures, with how each was measured, are on the average reaction time page, and what reaction time is explains the parts of a response.
Sources
- Freymiller, Whitford, McGowan, Higham, Clark. Springing into action: comparing escape responses between bipedal and quadrupedal rodents. Ecology and Evolution 14(9):e70292 (2024). doi:10.1002/ece3.70292. https://doi.org/10.1002/ece3.70292 (read: full text, checked Nov 8, 2026)
- Penning, Sawvel, Moon. Debunking the viper's strike: harmless snakes kill a common assumption. Biology Letters 12(3):20160011 (2016). doi:10.1098/rsbl.2016.0011. https://doi.org/10.1098/rsbl.2016.0011 (read: full text, checked Nov 8, 2026)
- May, Little, Saylor. Loudness perception in the domestic cat: reaction time estimates of equal loudness contours and recruitment effects. Journal of the Association for Research in Otolaryngology 10(2):295-308 (2009). doi:10.1007/s10162-009-0157-z. https://doi.org/10.1007/s10162-009-0157-z (read: full text, checked Nov 8, 2026)
- Higham, Clark, Collins, Whitford, Freymiller. Rattlesnakes are extremely fast and variable when striking at kangaroo rats in nature: three-dimensional high-speed kinematics at night. Scientific Reports 7:40412 (2017). doi:10.1038/srep40412. https://doi.org/10.1038/srep40412 (read: full text, checked Nov 8, 2026)
- Woods, Wyma, Yund, Herron, Reed. Factors influencing the latency of simple reaction time. Frontiers in Human Neuroscience 9:131 (2015). doi:10.3389/fnhum.2015.00131. https://doi.org/10.3389/fnhum.2015.00131 (read: full text, checked Nov 8, 2026)
- Patek, Baio, Fisher, Suarez. Multifunctionality and mechanical origins: ballistic jaw propulsion in trap-jaw ants. Proceedings of the National Academy of Sciences 103(34):12787-12792 (2006). doi:10.1073/pnas.0604290103. https://doi.org/10.1073/pnas.0604290103 (read: full text, checked Nov 8, 2026)
- Cox, Schmidt, Modarres-Sadeghi, Patek. A physical model of the extreme mantis shrimp strike: kinematics and cavitation of Ninjabot. Bioinspiration & Biomimetics 9(1):016014 (2014). doi:10.1088/1748-3182/9/1/016014. https://doi.org/10.1088/1748-3182/9/1/016014 (read: abstract only, checked Nov 8, 2026)
- deVries, Murphy, Patek. Strike mechanics of an ambush predator: the spearing mantis shrimp. Journal of Experimental Biology 215(24):4374-4384 (2012). doi:10.1242/jeb.075317. https://doi.org/10.1242/jeb.075317 (read: abstract only, checked Nov 8, 2026)
- Patek, Korff, Caldwell. Deadly strike mechanism of a mantis shrimp. Nature 428:819-820 (2004). doi:10.1038/428819a. https://doi.org/10.1038/428819a (read: abstract only, checked Nov 8, 2026)
- Card, Dickinson. Visually mediated motor planning in the escape response of Drosophila. Current Biology 18(17):1300-1307 (2008). doi:10.1016/j.cub.2008.07.094. https://doi.org/10.1016/j.cub.2008.07.094 (read: abstract only, checked Nov 8, 2026)
- Aiken, Loop. Visual reaction time of cats to different spatial frequencies. Visual Neuroscience 5(6):557-564 (1990). doi:10.1017/S0952523800000717. https://doi.org/10.1017/S0952523800000717 (read: abstract only, checked Nov 8, 2026)
Each source was found by its DOI and read on Nov 8, 2026, either in full or, where marked, in the abstract only; what we say about an abstract-only source goes no further than the abstract. Values are as the authors print them.