RGB to LCh | Color Code Converter | Color Conversion
Online RGB to LCh tool: enter a RGB color value to convert it to LCh in real time, with one-click copy of the result. Free and no registration required.
RGBEnter or adjust the color values
rgba(255, 87, 51, 1)
LCh
lch(60.18% 82.49 41.2)
L
60.18
C
82.49
H
41.2
All Color Conversion Combinations
132 itemsAbout RGB to LCh
RGB to LCh is a free online tool that converts RGB to LCh, helping you quickly convert colors and switch between formats in web design, front-end development, and graphic design. RGB is Represents color through the values of the red, green, and blue channels, each ranging from 0 to 255. LCh is The polar form of Lab, describing color with lightness L, chroma C, and hue H. At its core, RGB to LCh takes a color value expressed in RGB and converts it into LCh using a mathematical algorithm. The tool shows the result as both a visual color swatch and a complete CSS string, and you can copy it to the clipboard with a single click—no manual calculation or lookup tables required. This makes color code conversion fast, accurate, and reproducible, and it is suitable for designers, front-end developers, UI engineers, and anyone else who works with color.
What Is RGB to LCh
RGB represents color through the values of the red, green, and blue channels. Each channel ranges from 0-255, and the combination of the three channels covers roughly 16.77 million colors, making it the foundational color model for screen display. LCh is the polar form of Lab, describing color with lightness (L), chroma (C), and hue (H). It is more intuitive than Lab and closer to the way HSL is used. First convert RGB to XYZ and Lab, then turn a and b into polar coordinates: C = √(a²+b²) and H = atan2(b, a).
How to Use RGB to LCh
Using this RGB to LCh tool is very simple and takes just three steps. First, select RGB from the "Source Color Unit" dropdown on the left (it is selected by default), and enter the RGB value you want to convert in the input card. Second, select LCh from the "Target Color Unit" dropdown on the right; the tool instantly calculates and displays the corresponding LCh value, along with a color swatch preview and the complete CSS string, so you can confirm the color and format at a glance. Third, once you are happy with the result, click the "Copy" button to copy the LCh value to your clipboard and paste it straight into your code or design software. If you picked the wrong source or target unit, click the "⇄" button in the middle to swap them with one click. The whole process requires no registration and no data upload—all calculations run locally in your browser.
Use Cases for RGB to LCh
Use this when generating a color scale with the same hue but different chroma in a design system. Screen display, Canvas drawing, and any situation where a program needs to compute colors dynamically (such as generating a heat map from numeric data). Generating color scales in design systems, situations where only the chroma changes while the hue stays fixed, and modern CSS color schemes.
How RGB to LCh Works
First convert RGB to XYZ and Lab, then turn a and b into polar coordinates: C = √(a²+b²) and H = atan2(b, a). RGB is an additive model: the higher the channel values, the brighter the color. When all three channels are 0 the result is black, and when all are 255 it is white. Every pixel on a screen is formed by mixing red, green, and blue subpixels at different brightness levels. LCh and Lab convert to each other losslessly: L stays the same, C = √(a²+b²), and H = atan2(b, a). This turns the two orthogonal chroma axes into "chroma + hue", which fits how humans think.
Tips for Using RGB to LCh
The reference point for H in LCh differs from that in HSL, so the same visual hue has a different number; recalibrate when migrating across models. RGB is easy for programs to compute and iterate on, but the human eye finds it hard to interpret what a given set of numbers will look like, so it suits machine processing more than manual color adjustment. The reference point for H in LCh differs from that in HSL, so the same visual hue has different numbers in LCh and HSL. Migrating directly from HSL to LCh requires recalibrating the hue.
Frequently Asked Questions (FAQ)
Are LCh and Lab equivalent?
Yes. LCh is the polar form of Lab; only the description differs.
Can the C in LCh be very large?
Yes. C has no theoretical upper limit, but the part outside the sRGB gamut cannot be displayed accurately on screen.
Does RGB to LCh lose information?
No. As long as the original color is within the sRGB gamut, the conversion is lossless.
Why is the RGB range 0-255?
Because each channel is represented by 8 binary bits, and 2^8 = 256, so the range is 0-255.
What is the difference between RGB and RGBA?
RGBA adds an Alpha transparency channel on top of RGB, with a value from 0-1 that represents opacity.
Both LCh and HSL can adjust hue, so what is the difference?
The hue in HSL is perceptually uneven, so the same angular difference looks different under different hues. The hue in LCh is more perceptually uniform and better suited to building color scales.
Which is easier to use, LCh or Lab?
Use Lab for mathematical computation and LCh for manual color adjustment. The two are equivalent; only the coordinate form differs.
Can I convert in the opposite direction?
Yes. You can go directly to the "LCh to RGB" page, or click the "⇄" swap button in the middle of the current page to exchange the source and target units and convert in the opposite direction. The reverse conversion is just as precise, because the color conversion math is reversible.
Can I use the conversion results commercially?
Yes. Color values are numerical information and involve no copyright issues, so you are free to use the conversion results in websites, apps, design work, or commercial projects without authorization or attribution. Do note, however: if the original color comes from material that someone else holds the copyright to, using the color itself is unrestricted, but the copyright to the original material still belongs to its author.