Gamut Calculator
What is the CIE 1931 xy Gamut Calculator?
The CIE 1931 xy Gamut Calculator is an essential tool for display engineers and color scientists to evaluate the color performance of LCD panels and LED backlight systems. Developed by Shenzhen Samfong OPTO, this free online calculator enables precise measurement and comparison of color gamut coverage against industry-standard reference color spaces.
Key Features
- Gamut Ratio Calculation — Compare your device's color triangle area against a reference standard to determine the percentage ratio.
- Gamut Coverage Calculation — Measure the actual overlapping area between your device gamut and the reference, providing a more accurate representation of usable color range.
- Correlated Color Temperature (CCT) — Calculate the white point color temperature in Kelvin using the Robertson 1968 method.
- Duv Measurement — Determine the distance above or below the Planckian locus, critical for assessing white point accuracy.
- Interactive CIE 1931 Chromaticity Diagram — Visualize both reference and device color triangles on the standard horseshoe diagram with real-time rendering.
Supported Reference Standards
| Standard | Red (x,y) | Green (x,y) | Blue (x,y) | White (x,y) |
|---|---|---|---|---|
| sRGB / BT.709 | 0.6400, 0.3300 | 0.3000, 0.6000 | 0.1500, 0.0600 | 0.3127, 0.3290 |
| NTSC 1953 | 0.6700, 0.3300 | 0.2100, 0.7100 | 0.1400, 0.0800 | 0.3100, 0.3160 |
| Adobe RGB | 0.6400, 0.3300 | 0.2100, 0.7100 | 0.1500, 0.0600 | 0.3127, 0.3290 |
| DCI-P3 | 0.6800, 0.3200 | 0.2650, 0.6900 | 0.1500, 0.0600 | 0.3140, 0.3510 |
| BT.2020 | 0.7080, 0.2920 | 0.1700, 0.7970 | 0.1310, 0.0460 | 0.3127, 0.3290 |
How to Use the Calculator
- Select a Reference Standard — Choose from the preset dropdown (sRGB, NTSC, Adobe RGB, DCI-P3, or BT.2020) and click "Load Preset" to populate the reference CIE xy coordinates.
- Enter Device Coordinates — Input your display's measured R, G, B, and White point CIE 1931 xy values in the Device section. Alternatively, click "Copy from reference" to use the reference values for testing.
- Calculate — Click the "Calculate" button to compute gamut ratio, coverage, CCT, and Duv. The chromaticity diagram will render both color triangles and their intersection area.
- Analyze Results — Gamut Ratio above 100% means your device exceeds the reference standard. Gamut Coverage shows the actual overlap percentage. CCT indicates white point warmth, and Duv shows deviation from the Planckian locus.
Understanding the Results
Gamut Ratio vs. Gamut Coverage: Gamut Ratio compares the total area of your device triangle to the reference, which can exceed 100% if your device has a wider color space. Gamut Coverage measures only the overlapping area, providing a more conservative and often more meaningful metric for content compatibility.
CCT (Correlated Color Temperature): Expressed in Kelvin (K), this value describes the warmth or coolness of your display's white point. Lower values (3000-4000K) appear warm/yellowish, while higher values (7000-10000K) appear cool/bluish. The standard D65 white point corresponds to approximately 6500K.
Duv: This metric indicates how far your white point deviates from the ideal Planckian (black body) locus. A Duv of 0 means the white point sits exactly on the locus. Positive values indicate a greenish tint, while negative values indicate a pinkish tint. For display manufacturing, keeping |Duv| below 0.005 is generally recommended.
About Shenzhen Samfong OPTO
Shenzhen Samfong OPTO is a leading manufacturer of high-performance LCD displays and LED backlight solutions. With expertise spanning industrial, automotive, medical, aerospace, and consumer electronics segments, Samfong delivers precision display modules with exceptional color accuracy and reliability. The CIE 1931 xy Gamut Calculator is provided as a free resource for the display engineering community.
Try the calculator now at Shenzhen Samfong OPTO CIE 1931 xy Gamut Calculator.
