Refresh Rate Calculator

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.refresh-calc-container { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; max-width: 800px; margin: 20px auto; padding: 25px; border: 1px solid #e1e1e1; border-radius: 12px; background-color: #ffffff; box-shadow: 0 4px 6px rgba(0,0,0,0.05); } .refresh-calc-header { text-align: center; margin-bottom: 30px; } .refresh-calc-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-bottom: 25px; } .refresh-calc-field { display: flex; flex-direction: column; } .refresh-calc-field label { font-weight: 600; margin-bottom: 8px; color: #333; } .refresh-calc-field input, .refresh-calc-field select { padding: 12px; border: 1px solid #ccc; border-radius: 6px; font-size: 16px; } .refresh-calc-button { background-color: #007bff; color: white; border: none; padding: 15px 25px; border-radius: 6px; font-size: 18px; font-weight: bold; cursor: pointer; width: 100%; transition: background-color 0.2s; } .refresh-calc-button:hover { background-color: #0056b3; } .refresh-calc-result { margin-top: 30px; padding: 20px; background-color: #f8f9fa; border-radius: 8px; border-left: 5px solid #007bff; } .result-item { display: flex; justify-content: space-between; padding: 10px 0; border-bottom: 1px solid #eee; } .result-item:last-child { border-bottom: none; } .result-label { font-weight: 600; color: #555; } .result-value { font-weight: 700; color: #007bff; font-size: 18px; } .refresh-article { margin-top: 40px; line-height: 1.6; color: #444; } .refresh-article h2 { color: #222; border-bottom: 2px solid #007bff; padding-bottom: 8px; } .refresh-article h3 { margin-top: 25px; color: #333; } @media (max-width: 600px) { .refresh-calc-grid { grid-template-columns: 1fr; } }

Refresh Rate & Bandwidth Calculator

Calculate frame time, data rates, and cable requirements for your display.

8-bit (Standard) 10-bit (HDR) 12-bit (Professional) 16-bit (Ultra High)
4:4:4 / RGB (Uncompressed) 4:2:2 4:2:0
Frame Time: –
Raw Data Rate: –
Effective Bandwidth (with Overhead): –
Recommended Cable: –

Understanding Refresh Rate and Display Bandwidth

The refresh rate of a monitor or TV, measured in Hertz (Hz), represents the number of times per second the screen updates the displayed image. A higher refresh rate results in smoother motion, which is crucial for gaming, sports, and professional video editing. However, pushing more frames at higher resolutions requires significant data bandwidth.

How Refresh Rate Affects Frame Time

Frame time is the duration it takes for a single frame to be displayed. It is the mathematical inverse of the refresh rate. For example, a standard 60Hz monitor has a frame time of 16.67 milliseconds (ms). If you upgrade to a 144Hz monitor, the frame time drops to approximately 6.94ms, providing a much more responsive feel and reduced motion blur.

Calculating Bandwidth Requirements

To calculate the required bandwidth for a specific display setup, you must consider several factors:

  • Resolution: The total number of pixels (Width x Height).
  • Refresh Rate: How many times those pixels are updated per second.
  • Color Depth: The number of bits used to represent the color of a single pixel. Standard is 8-bit, while HDR content often uses 10-bit or 12-bit.
  • Chroma Subsampling: A compression method that reduces color information (e.g., 4:2:0) to save bandwidth at the cost of some color accuracy.

Typical Standards and Cable Limits

If your calculation shows a required bandwidth higher than your cable's capacity, you may experience flickering, a black screen, or be forced to use lower color settings. Common limits include:

  • HDMI 2.0: Up to 18 Gbps (Supports 4K at 60Hz).
  • HDMI 2.1: Up to 48 Gbps (Supports 4K at 120Hz or 8K at 60Hz).
  • DisplayPort 1.4: Up to 32.4 Gbps.
  • DisplayPort 2.1: Up to 80 Gbps.

Realistic Example

If you are running a 4K resolution (3840 x 2160) at 144Hz with 10-bit color depth and 4:4:4 chroma, the raw data rate exceeds 35 Gbps. Once you factor in blanking intervals (timing overhead), you need approximately 39.5 Gbps, meaning an HDMI 2.1 or DisplayPort 2.1 cable is mandatory for this configuration.

function calculateRefreshMetrics() { var width = parseFloat(document.getElementById('resWidth').value); var height = parseFloat(document.getElementById('resHeight').value); var hz = parseFloat(document.getElementById('refreshRate').value); var depth = parseFloat(document.getElementById('colorDepth').value); var chromaFactor = parseFloat(document.getElementById('chroma').value); var overhead = parseFloat(document.getElementById('overhead').value); if (isNaN(width) || isNaN(height) || isNaN(hz) || isNaN(depth)) { alert("Please enter valid numerical values."); return; } // Frame Time in ms var frameTime = (1000 / hz).toFixed(2); // Bits per pixel based on chroma // 4:4:4 = 3 components, 4:2:2 = 2 components equivalent, 4:2:0 = 1.5 components equivalent var bpp = depth * chromaFactor; // Raw Data Rate in Gbps (Width * Height * Hz * BPP) var rawRate = (width * height * hz * bpp) / 1000000000; // Effective Bandwidth including overhead var totalBandwidth = rawRate * (1 + (overhead / 100)); // Determine Recommended Cable var cable = "DisplayPort 2.1 / HDMI 2.1"; if (totalBandwidth <= 4.95) { cable = "HDMI 1.2 / High Speed HDMI"; } else if (totalBandwidth <= 10.2) { cable = "HDMI 1.4 / DisplayPort 1.2"; } else if (totalBandwidth <= 18.0) { cable = "HDMI 2.0 / DisplayPort 1.2"; } else if (totalBandwidth <= 32.4) { cable = "DisplayPort 1.4 / HDMI 2.1"; } else if (totalBandwidth <= 48.0) { cable = "HDMI 2.1 / DisplayPort 2.1"; } // Display results document.getElementById('outFrameTime').innerText = frameTime + " ms"; document.getElementById('outDataRate').innerText = rawRate.toFixed(2) + " Gbps"; document.getElementById('outBandwidth').innerText = totalBandwidth.toFixed(2) + " Gbps"; document.getElementById('outCable').innerText = cable; document.getElementById('refreshResult').style.display = "block"; }

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