Pixel Clock Calculator

Calculate pixel clock frequency for custom resolutions and monitor overclocking. Essential for CRU (Custom Resolution Utility) and display timing configuration.

Pixel Clock

148.50 MHz

H Total

2200 px

V Total

1125 lines

Bandwidth

~3.56 Gbps

TC
Created by TechCalc Team
•Published: 2025-02-01•Updated: 2025-12-01

What is Pixel Clock?

Pixel Clock (or dot clock) is the frequency at which pixels are transmitted to a display, measured in MHz (megahertz). It determines the maximum resolution and refresh rate combination your display can support.

Pixel Clock Formula

Pixel Clock (MHz) = (H_Total × V_Total × Refresh Rate) ÷ 1,000,000

H_Total (Horizontal Total)

Horizontal Resolution + Horizontal Blanking (front porch, sync, back porch). For 1920×1080, typical H_Total is around 2200 pixels.

V_Total (Vertical Total)

Vertical Resolution + Vertical Blanking (front porch, sync, back porch). For 1920×1080, typical V_Total is around 1125 lines.

Why Pixel Clock Matters

Every display interface (HDMI, DisplayPort) has a maximum pixel clock it can handle. If your desired resolution and refresh rate combination exceeds this limit, the signal won't work. Understanding pixel clock helps you:

  • Verify if your cable supports your desired resolution/refresh rate
  • Create custom resolutions using CRU (Custom Resolution Utility)
  • Overclock your monitor to higher refresh rates safely
  • Troubleshoot display issues and black screens

Common Pixel Clock Examples

ResolutionRefresh RatePixel Clock
1920×108060 Hz148.5 MHz
1920×1080144 Hz~346 MHz
2560×1440144 Hz~587 MHz
3840×216060 Hz~594 MHz
3840×2160120 Hz~1188 MHz

Use Cases

Custom Resolution Utility (CRU)

Create custom display modes for monitors that don't advertise all supported resolutions.

Monitor Overclocking

Push refresh rates beyond stock specifications. Many 60Hz monitors can reach 75Hz.

HDMI/DP Bandwidth Check

Verify your signal fits within cable and port bandwidth limits before purchasing.

EDID Editing

Modify display identification data for compatibility with specific hardware.

Frequently Asked Questions

What is Pixel Clock?

Pixel Clock (also called dot clock) is the frequency at which pixels are transmitted to the display. It determines how fast the display can refresh and is measured in MHz.

How is Pixel Clock calculated?

Pixel Clock = (Horizontal Total × Vertical Total × Refresh Rate) ÷ 1,000,000. The totals include blanking intervals (front porch, sync pulse, back porch).

Why do I need to calculate Pixel Clock?

Pixel clock calculation is essential for CRU (Custom Resolution Utility), monitor overclocking, and verifying GPU/display compatibility with HDMI or DisplayPort bandwidth limits.

What is the maximum pixel clock for HDMI 2.0?

HDMI 2.0 supports up to 600 MHz pixel clock (18 Gbps bandwidth). This allows 4K@60Hz or 1080p@240Hz. For higher refresh rates at 4K, you need HDMI 2.1 (1200 MHz / 48 Gbps).

Can I overclock my monitor refresh rate?

Yes, many monitors can be overclocked using CRU (Custom Resolution Utility). Calculate the required pixel clock first to ensure it does not exceed your cable and GPU limits. Start with small increments (5-10 Hz) and test stability.

Bandwidth Limits

HDMI 1.4
10.2 Gbps
340 MHz
HDMI 2.0
18 Gbps
600 MHz
HDMI 2.1
48 Gbps
1200 MHz
DisplayPort 1.2
17.28 Gbps
540 MHz
DisplayPort 1.4
25.92 Gbps
810 MHz
DisplayPort 2.0
80 Gbps
2500 MHz

💡 Pro Tip:

When overclocking your monitor, start with small increments (5-10 Hz) and test stability before pushing further. Always verify your cable supports the required bandwidth.

Related Tools

→ PPI Calculator→ Aspect Ratio Calculator→ Download Time Calculator