Input Lag Test
Click when the screen flashes to measure click-to-visual latency. Run 10 trials for an average input lag estimate.
Click to start
What is monitor input lag?
Input lag is the delay between a user action (mouse click, keystroke) and a visible change on the monitor. It combines signal processing in the display, monitor electronics, and the system render pipeline. Most gaming monitors target 1-5ms input lag; budget and TV panels can reach 20-100ms.
Input lag vs response time
These are often confused. Response time (GtG, MPRT) is how fast a pixel changes color — it affects ghosting. Input lag is how fast the monitor displays the signal it receives after processing it. A monitor can have fast GtG but high input lag due to extensive image processing.
How to reduce input lag
- Enable Game Mode in your monitor OSD — disables post-processing
- Set display to native resolution — scaling adds latency
- Use DisplayPort over HDMI where possible
- Disable HDR in Windows if not needed — HDR pipeline adds processing
- Use high refresh rate — each frame has a shorter display window
- Enable VRR / G-Sync / FreeSync for consistent frame pacing
Typical input lag by display type
- Gaming monitors (Game Mode on): 1–5 ms
- IPS monitors (no Game Mode): 5–15 ms
- Budget LCD: 15–40 ms
- TVs with Game Mode: 8–15 ms
- TVs without Game Mode: 60–150 ms
Note: browser-based tests include human reaction time and system latency. For hardware-accurate input lag, use a Leo Bodnar meter or HDMI latency tester. This tool gives a relative comparison between sessions.
Also try our Reaction Time Test and What Is Input Lag guide.
Testing guide
How to understand input lag test results
A browser input lag test measures the visible click-to-change path on your current device and browser. It is useful for comparing settings, but absolute monitor latency still requires hardware tools such as a photodiode or high-speed camera.
Best for
- Comparing game mode, HDR mode, scaling, and post-processing settings.
- Spotting large latency changes after switching cables, docks, refresh rates, or display modes.
- Building a repeatable baseline for your own gaming or desktop setup.
How to run the test
- 1Use the same mouse, browser, monitor mode, and refresh rate for each comparison.
- 2Run multiple attempts and compare averages rather than one single click.
- 3Disable extra processing such as noise reduction, motion smoothing, and unnecessary scaling.
- 4Compare results before and after enabling game mode or low-latency mode.
How to read the result
Lower and more consistent values usually feel more responsive.
Large variance can come from system load, browser scheduling, USB polling, wireless devices, or power saving.
Higher refresh rate often reduces the frame interval part of end-to-end latency.
Related tools and guides
Frequently asked questions
Can a browser test measure exact monitor input lag?
No. It can compare your current input-to-visual response path, but exact monitor signal latency requires dedicated hardware measurement.
What settings reduce input lag?
Use the native resolution, highest stable refresh rate, game mode or low-latency mode, and disable unnecessary post-processing such as motion smoothing or noise reduction.
Does HDR increase input lag?
It can on some displays because HDR tone mapping and local dimming may add processing. Compare HDR on and off if latency matters for competitive gaming.