Input Lag Calculator
Calculate total system latency from peripherals to display output
Set Your Refresh Rate
Select your monitor’s refresh rate. Higher refresh rates like 144Hz or 240Hz reduce frame time and overall latency.
Enter Monitor Input Lag
Check your monitor’s specs or reviews for input lag. Gaming monitors typically have 1-5ms, while regular monitors may have 10-20ms.
Select USB Polling Rate
Choose your mouse/keyboard polling rate. 1000Hz is standard for gaming peripherals. Higher rates like 8000Hz reduce input latency further.
Estimate Render Latency
1 frame is ideal with unlimited FPS. V-Sync adds 1-2 frames. Heavy GPU load or frame limiting increases render queue.
What is Input Lag?
Total time from your physical input (mouse click, key press) to the result appearing on screen. Includes peripheral, PC processing, and display latency.
Frame Time Impact
At 60Hz, each frame takes 16.67ms. At 240Hz, it’s only 4.17ms. Higher refresh rates significantly reduce this component.
V-Sync and Latency
Traditional V-Sync adds 1-3 frames of latency. Use G-Sync/FreeSync or NVIDIA Reflex to minimize input lag while avoiding tearing.
Competitive Standards
Pro esports players aim for under 20ms total latency. Casual gaming is comfortable under 50ms. Above 100ms becomes noticeable.
Frequently Asked Questions
What is a good input lag for gaming?
Below 5 ms of monitor input lag is considered excellent for competitive gaming. Most modern gaming monitors measure 1-5 ms of display-side processing lag in Game Mode. Added to system latency (GPU render time + frame buffer delay), total system input latency typically ranges from 10-30 ms. For reference, the human perception threshold for latency in manual control tasks is approximately 50-100 ms; below 20 ms feels near-instantaneous.
How does refresh rate reduce input lag?
At 60 Hz, the monitor updates every 16.67 ms — the maximum time an action can wait before the next frame is displayed. At 144 Hz, that window is 6.94 ms; at 240 Hz, 4.17 ms. Even if the GPU renders instantly, input registered just after a scan-out must wait for the next frame. Higher refresh rate reduces this wait time, lowering average input lag by roughly (1000 / Hz) / 2 ms — half the frame interval.
Does V-Sync increase input lag?
Traditional V-Sync adds 1-2 frames of buffering to ensure complete frames are displayed, introducing 16-33 ms of additional input lag at 60 Hz. This latency is perceptible in fast games. VRR (G-Sync/FreeSync) eliminates tearing without frame buffering, maintaining low input lag while preventing the visual artifacts of non-synced display. Nvidia Reflex (in supported games) further reduces pre-render GPU queue depth, cutting system latency by 30-50% on compatible hardware.
What is the difference between input lag and response time?
Input lag is the total system latency from input to visible change on screen — a system-level metric. Response time (GtG or MPRT) is the time for a pixel to physically change state — a panel-level metric. Both contribute to the gaming experience but are independent: a monitor can have 1 ms GtG yet 20 ms input lag due to internal image processing. Always measure input lag separately using tools like Leo Bodnar’s tester or high-speed camera comparison.
Why does 'Game Mode' on a monitor reduce input lag?
Game Mode (or Low Input Lag mode) bypasses or simplifies the monitor’s internal image processing pipeline — disabling features like dynamic contrast, overdrive enhancement, framerate upscaling (Motion Interpolation), and color enhancement filters. These processors add sequential processing frames that delay the signal. Disabling them can reduce monitor-side processing latency from 30-60 ms to 1-5 ms on many panels.