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We tried to group together the more usual questions we receive about using and interpreting this site data and services. These FAQs are all related to the EasyRGB site and the way we specifically handle color information. If you are searching for more generic information about color, on the Net there are several good sites devoted to color science, physics, psychology, physiology and technology. Check our Links page for a list of handy color FAQ references.

What can I do using the services of this site?

How accurate are on-screen colors?

How are color standards measured?

How color measures are stored in the EasyRGB database?

How is the closest color (best match) calculated?

Why HLS/HSL/HSB/HSV data is not supported?

HLS, HSL, HSB and HSV are used to specify numerical Hue, Lightness (or Brightness) and Saturation in place or as a complement of the standard RGB values.
There are two major problems related to these color spaces:
1. There is no standard defining the way to compute these value. Specially the Lightness (or Brightness) is usually calculated as L = (R + G + B) / 3, versus a more realistic implementation (L = xr * R + xg * G + xb * B) that involves hue-dependent different computations.
2. The mentioned simple Lightness calculation conflict badly with the properties of color vision. Also Hue linearity is a problem in this space definition
For the above reasons this site does not directly support these color spaces.
As a reference, the standard Windows conversion algorithm is anyway posted on our math page.


Is any gamma correction applied to the displayed colors?

Why is a 45 (not a sphere based) spectrophotometer used?

Is possible to add a new color collection to the color matching list?

What is the required color resolution for this site?

Is any compatibility problem associated with old browsers?

Why printed colors are not consistent with my monitor?