144Hz vs 240Hz Monitors: Does Higher Refresh Rate Improve Reaction Time?

Quick Answer

This guide turns an abstract idea about reaction speed into something you can notice, measure, and improve. The fastest way to use it is to read the benchmark first, compare it with your own context, then run a related BrainRivals test under the same conditions for a cleaner before-and-after signal.

Key takeaways

• Start with the practical benchmark, not the trivia.
• Treat one score as a snapshot and repeated scores as the real signal.
• Use the Reaction Time as the next measurable step.

How to Use This Guide

Use the article in three passes: scan the quick answer, check the tables or examples that match your situation, then pick one action to test this week. That keeps the article useful even if you only have a few minutes, while still giving you enough detail to come back for deeper context.

The refresh rate debate rages on in gaming forums. Jump from 60Hz to 144Hz? Noticeable. Jump from 144Hz to 240Hz? That's where things get murky. Let's look at what actually happens physiologically and physically.

The Physics: Frame Time and Input Lag

Frame time is the inverse of refresh rate. It's how often the monitor updates:

Refresh Rate	Frame Time	Input Lag Window
60Hz	16.67ms	0-16.67ms
75Hz	13.33ms	0-13.33ms
144Hz	6.94ms	0-6.94ms
165Hz	6.06ms	0-6.06ms
240Hz	4.17ms	0-4.17ms
360Hz	2.78ms	0-2.78ms

The absolute maximum input lag improvement from going 144Hz to 240Hz is 2.77ms. In theory, this can help. In practice, you're already well below human perception for simple reaction tasks.

What Happens Between the GPU and Your Eyes

Here's the full latency chain when you click:

1. Mouse transmits click: 0-8ms (depending on polling rate)
2. OS receives input: 0-5ms
3. Browser event fires: 2-10ms
4. GPU renders frame: 1-5ms
5. Monitor displays frame: 0-4.17ms (at 240Hz) vs 0-6.94ms (at 144Hz)
6. Your eye perceives it: ~50-100ms (biological)

The monitor refresh rate contributes less than 7ms to the total latency chain. Your brain's biological response time adds 50-100ms on its own.

Persistence of Vision and Motion Blur

This is where higher refresh rates genuinely help:

Persistence of vision is how long an image stays in your visual cortex. Your brain integrates visual information over ~13-40ms. At 60Hz, each frame is on-screen for 16.67ms. By the time you see it, the next frame is already rendering. This creates perceived motion blur.

At 144Hz, the gap shrinks to 6.94ms. At 240Hz, it shrinks to 4.17ms. For fast-moving objects, higher refresh rates genuinely reduce blur.

But for a simple reaction time test where you're clicking a static or slowly-moving target? The blur reduction doesn't matter.

The Human Visual System's Theoretical Limits

There's a persistent claim that humans can't see above 60Hz. This is wrong. Humans can detect differences up to around 1000Hz in controlled laboratory conditions. However:

• Most people plateau their perceptual benefit around 144-165Hz
• Elite athletes and esports players report noticeable differences up to 240Hz
• Beyond 240Hz, improvements become imperceptible for most humans in practical tasks

For reaction time tests, you're not tracking fast movement or benefiting from motion smoothness. The advantage of 240Hz is marginal.

Refresh Rate vs Input Lag: Separate Issues

Refresh rate and input lag are related but not identical:

• Refresh rate = how often the monitor redraws (60Hz, 144Hz, etc.)
• Input lag = delay between your input and screen response

A 144Hz monitor with 40ms input lag is worse than a 60Hz monitor with 10ms input lag.

The better metric is total system latency, which includes:

• Monitor latency: 5-50ms (varies by panel technology)
• GPU rendering: 5-15ms
• Driver overhead: 2-10ms
• Display transmission: 0-10ms

A gaming monitor marketed as "1ms response time" is referring to pixel response time (how fast colors change), not input lag. Read the reviews.

Real-World Reaction Time Impact

Let's test with hard numbers:

60Hz monitor with 30ms input lag: Total lag = 30 + 0-16.67ms = 30-46.67ms 144Hz monitor with 15ms input lag: Total lag = 15 + 0-6.94ms = 15-21.94ms 240Hz monitor with 10ms input lag: Total lag = 10 + 0-4.17ms = 10-14.17ms

If you improve from 60Hz to 144Hz, you might gain 10-30ms of latency reduction depending on monitor quality. This could improve a 250ms reaction time by 4-12%.

From 144Hz to 240Hz? You're looking at 5-10ms of potential improvement. That's 2-4% for the average person. Professional esports players might measure this. Most people won't.

Should You Upgrade to 240Hz?

The honest answer: It depends on your current monitor quality, not just refresh rate.

Upgrade to 144Hz if: You're on 60Hz. The improvement is substantial (10-30ms) and worth it.

Upgrade to 240Hz if:

• You have a 144Hz monitor with poor input lag performance (>20ms)
• You're competing in esports and microseconds matter
• You can maintain 240+ fps in your games (otherwise, the high refresh rate is wasted)

Don't upgrade to 240Hz if:

• Your current 144Hz monitor has good reviews (low input lag)
• You're testing on BrainRivals (the web infrastructure adds more latency than a refresh rate upgrade will save)
• You can't reliably hit 240+ fps in your games

Panel Technology Matters More Than You Think

Not all 144Hz monitors are equal. IPS panels (better colors) vs TN panels (faster response) vs VA panels (better contrast).

For reaction time testing, TN panels are the fastest but often have worse picture quality. IPS and VA panels can have 5-15ms longer response times but are better for general use.

The panel technology you choose will have more impact on your latency than the difference between 144Hz and 240Hz.

The Optimal Setup for Cognitive Tests

Rather than chasing 240Hz:

1. Get a 144Hz monitor with low input lag (under 15ms, ideally under 10ms)
2. Prioritize panel response time (IPS/TN under 5ms)
3. Ensure your GPU can handle 144+ fps in whatever you're testing
4. Optimize your PC settings (Windows power plan, driver updates)

This will cost $200-400 and deliver 90% of the benefit of a $600 240Hz monitor.

Final Verdict

The jump from 60Hz to 144Hz is transformative. The jump from 144Hz to 240Hz is incremental. For BrainRivals reaction time tests specifically, monitor refresh rate is less important than OS optimization, browser choice, and eliminating background processes.

Your reaction time improvement ceiling is much higher through software tweaks than hardware additions at this point.

Test your reaction time on your current setup first. Take the Reaction Time challenge and run the Aim Trainer to establish a baseline before investing in new hardware.

Try It on BrainRivals

Reading about the concept is useful, but a repeatable score is more actionable. Run the Reaction Time and Aim Trainer tests, save your result, then repeat under similar conditions later. The trend matters more than a single best attempt.