Response time explained: GtG vs MPRT
What 1 ms and 0.03 ms really measure, why brands' numbers don't line up, and how our monitors compare to their own frame time.
By Offerove Editorial TeamUpdated 2 min readResearch-based, not hands-on
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Response time is how fast a monitor's pixels change from one shade to another, usually quoted in milliseconds as gray-to-gray (GtG). Lower means less smearing behind moving objects. Brands measure it their own way, so treat the number as a rough guide and compare it with the monitor's refresh rate.
Response time is the small “ms” number next to the refresh rate on a monitor box. It decides how clean fast motion looks.
Here is what it measures, why brands’ numbers don’t always line up, and how our monitors compare. Specs are from each maker’s official page, as of November 2026.
What is response time?
Short answer: response time is how long a pixel takes to change color, in milliseconds. The common spec is gray-to-gray (GtG): the time to shift from one shade of gray to another. Slow pixels leave a faint smear behind moving objects.
ViewSonic calls GtG the standard figure on almost every spec sheet. A second figure, MPRT, measures how long each pixel stays visible. That one relates more to motion blur.
Why brands’ numbers don’t line up
Short answer: there is no single test method. Makers choose their own gray levels and overdrive settings, so one brand’s 1 ms may not match another’s. Treat a quoted number as a best case.
VESA built its ClearMR logo to fix this. It scores a Clear Motion Ratio, based on clear pixels versus blurry ones. VESA tests at default settings with backlight strobing off, and it limits overshoot, so blur tricks don’t inflate the score.
A response time only matters relative to the refresh rate. A pixel that finishes early in the frame looks sharp.
Our monitors: response time vs frame time
Short answer: our three OLED monitors list 0.03 ms, about 1% of a frame or less. Our IPS gaming monitors list 1 ms, around 16 to 18% of a frame. The 4K office monitor lists 4 ms, nearly half its frame.
Our math: divide the listed response time by the time between refreshes (1,000 divided by the refresh rate).
| Monitor | Panel | Response time | Refresh rate | Share of frame |
|---|---|---|---|---|
| Alienware AW2725DF | QD-OLED | 0.03 ms | 360 Hz | 1.1% |
| Samsung Odyssey OLED G6 | OLED | 0.03 ms | 360 Hz | 1.1% |
| LG UltraGear 27GS95QE | OLED | 0.03 ms | 240 Hz | 0.7% |
| AOC Q27G4X | Fast IPS | 1 ms | 180 Hz | 18% |
| ASUS ROG Strix XG27ACS | Fast IPS | 1 ms | 180 Hz | 18% |
| ASUS TUF Gaming VG27AQ3A | Fast IPS | 1 ms | 180 Hz | 18% |
| LG UltraGear 27GR75Q | IPS | 1 ms | 165 Hz | 16.5% |
| Dell S2725QC | IPS | 4 ms | 120 Hz | 48% |
The Dell is a 4K office monitor, not a gaming model, so 4 ms fits its job.
Read refresh rate explained and OLED vs Mini-LED next. For picks, see best monitors for PS5 and PC.
The picks, side by side
| Product | Response time | Refresh rate | Panel | Spec score |
|---|---|---|---|---|
| Alienware 27 360Hz QD-OLED Gaming Monitor (AW2725DF) | 0.03 ms | 360 Hz | QD-OLED | 8.0 |
| Samsung Odyssey OLED G6 (G60SD) 27 in | 0.03 ms | 360 Hz | OLED | 7.4 |
| LG UltraGear 27GS95QE | 0.03 ms | 240 Hz | OLED | 6.8 |
| AOC Q27G4X | 1 ms | 180 Hz | Fast IPS | 6.8 |
| ASUS ROG Strix XG27ACS | 1 ms | 180 Hz | Fast IPS | 6.5 |
| ASUS TUF Gaming VG27AQ3A | 1 ms | 180 Hz | Fast IPS | 6.1 |
| LG UltraGear 27GR75Q | 1 ms | 165 Hz | IPS | 6.2 |
| Dell 27 Plus 4K USB-C Monitor (S2725QC) | 4 ms | 120 Hz | IPS | 6.5 |
Specs from each maker's official page, checked Nov 9, 2026. Spec score formula: methodology.
How we chose
We explain response time using ViewSonic's and BenQ's official monitor explainers and VESA's ClearMR standard, then list the response times our monitors' makers state. The frame time comparison is our own arithmetic. Research-based, not tested in person. Our methodology.
FAQ
What does GtG mean?
Gray-to-gray, the time a pixel takes to shift from one shade of gray to another, and the figure on most spec sheets.
What is MPRT?
Moving picture response time, which measures how long a pixel stays visible and so relates to motion blur.
Is 1 ms response time good?
Yes, on our 180 Hz IPS monitors 1 ms is about 18% of the time between refreshes, which leaves most of each frame clean.
Why do OLED monitors list 0.03 ms?
OLED pixels switch very quickly, and all three OLED monitors in our catalog list 0.03 ms GtG from their makers.
Sources
- ViewSonic: What is response time for monitors? (opens in a new tab)
- BenQ: How is monitor response time measured? (opens in a new tab)
- VESA: New compliance test specification and logo program for motion blur (ClearMR) (opens in a new tab)
- Alienware 27 360Hz QD-OLED Gaming Monitor (AW2725DF): Alienware official specs (opens in a new tab)
- Samsung Odyssey OLED G6 (G60SD) 27 in: Samsung official specs (opens in a new tab)
- LG UltraGear 27GS95QE: LG official specs (opens in a new tab)
- AOC Q27G4X: AOC official specs (opens in a new tab)
- ASUS ROG Strix XG27ACS: ASUS official specs (opens in a new tab)
- ASUS TUF Gaming VG27AQ3A: ASUS official specs (opens in a new tab)
- LG UltraGear 27GR75Q: LG official specs (opens in a new tab)
- Dell 27 Plus 4K USB-C Monitor (S2725QC): Dell official specs (opens in a new tab)
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