RGB to OKLCH Converter
RGB in, OKLCH out — with the working shown.
To convert RGB to OKLCH, normalise the input, linearise the channels, move into the perceptual space, go polar, then check the gamut. For example, rgb(47 129 247) in RGB is oklch(61.82% 0.1935 258.33) in OKLCH.
This is a free RGB to OKLCH converter. Type or paste any red, green and blue channel values into the field above and the OKLCH value updates as you type, along with every other notation the web understands. OKLCH is OKLab in polar form — perceptual lightness, absolute chroma and a hue angle.
Conversions run entirely in your browser using the same color engine as the rest of the site: values round-trip through linear sRGB and CIE XYZ rather than through an approximation, so what you copy is accurate to the last digit the format can carry.
How to convert RGB to OKLCH
- Normalise the input. Read the RGB value and scale each component into the 0–1 range the maths expects.
- Linearise the channels. Undo the sRGB gamma curve, because the encoded 0–255 numbers are not proportional to light and averaging them directly is what makes gradients go muddy.
- Move into the perceptual space. Convert linear RGB into LMS cone responses, take the cube root, and apply the OKLab matrix.
- Go polar. Chroma is the distance from the neutral axis and hue is the angle, so C = √(a² + b²) and H = atan2(b, a).
- Check the gamut. Clamp anything that falls outside what an sRGB display can show, so the value you copy is the value you get.
Worked example: rgb(47 129 247) converts to oklch(61.82% 0.1935 258.33). That color is Dodger Blue, and the tool above shows each intermediate step for whatever value you enter.
Common RGB to OKLCH values
The twenty colors people look up most often, converted from RGB to OKLCH. Every row is computed by the same engine as the tool above.
| Color | RGB | OKLCH |
|---|---|---|
| White | rgb(255 255 255) | oklch(100% 0 0) |
| Black | rgb(0 0 0) | oklch(0% 0 0) |
| Red | rgb(255 0 0) | oklch(62.8% 0.2577 29.23) |
| Lime | rgb(0 255 0) | oklch(86.64% 0.2948 142.5) |
| Blue | rgb(0 0 255) | oklch(45.2% 0.3132 264.05) |
| Yellow | rgb(255 255 0) | oklch(96.8% 0.211 109.77) |
| Cyan | rgb(0 255 255) | oklch(90.54% 0.1546 194.77) |
| Magenta | rgb(255 0 255) | oklch(70.17% 0.3225 328.36) |
| Silver | rgb(192 192 192) | oklch(80.78% 0 0) |
| Gray | rgb(128 128 128) | oklch(59.99% 0 0) |
| Maroon | rgb(128 0 0) | oklch(37.67% 0.1546 29.23) |
| Olive | rgb(128 128 0) | oklch(58.07% 0.1266 109.77) |
| Green | rgb(0 128 0) | oklch(51.98% 0.1769 142.5) |
| Purple | rgb(128 0 128) | oklch(42.09% 0.1935 328.36) |
| Teal | rgb(0 128 128) | oklch(54.31% 0.0927 194.77) |
| Navy | rgb(0 0 128) | oklch(27.11% 0.1879 264.05) |
| Orange | rgb(255 165 0) | oklch(79.27% 0.171 70.67) |
| Pink | rgb(255 192 203) | oklch(86.77% 0.0735 7.09) |
| Gold | rgb(255 215 0) | oklch(88.68% 0.1822 95.33) |
| Crimson | rgb(220 20 60) | oklch(57.12% 0.2219 20.09) |
RGB and OKLCH, briefly
RGB is three channels from 0 to 255 describing how hard the display drives its red, green and blue subpixels. Valid range: 0–255 per channel.
OKLCH is OKLab in polar form — perceptual lightness, absolute chroma and a hue angle. Valid range: L 0–100%, C 0–0.37 in sRGB, H 0–360°.
OKLCH is worth learning if you have not. Unlike HSL, equal steps of its lightness channel look equal to the eye, which is what makes generated ramps and hover states behave predictably across every hue.
Frequently asked questions
How do you convert RGB to OKLCH?
1. Read the RGB value and scale each component into the 0–1 range the maths expects. 2. Undo the sRGB gamma curve, because the encoded 0–255 numbers are not proportional to light and averaging them directly is what makes gradients go muddy. 3. Convert linear RGB into LMS cone responses, take the cube root, and apply the OKLab matrix. 4. Chroma is the distance from the neutral axis and hue is the angle, so C = √(a² + b²) and H = atan2(b, a). 5. Clamp anything that falls outside what an sRGB display can show, so the value you copy is the value you get. The converter on this page does all of it as you type, and shows the working underneath.
What is rgb(255 0 0) in OKLCH?
Pure red, rgb(255 0 0), is oklch(62.8% 0.2577 29.23) in OKLCH. There is a table of twenty common colors converted to OKLCH further up this page.
What is rgb(47 129 247) in OKLCH?
rgb(47 129 247) converts to oklch(61.82% 0.1935 258.33). It is a dodger blue, and you can paste any other value into the field at the top of the page to convert it.
Is RGB to OKLCH conversion lossless?
Within sRGB, yes — converting to OKLCH and back returns the value you started with. The only rounding happens when a component is written out to a fixed number of decimal places.
Can I use OKLCH directly in CSS?
Yes. oklch(61.82% 0.1935 258.33) is valid CSS and works in every current browser. It is the modern choice, because it can also express colors outside sRGB on wide-gamut displays.
Does this RGB to OKLCH converter support transparency?
Alpha is preserved wherever the target notation can carry it — eight-digit hex, rgb() / a, hsl() / a and the modern CSS spaces all round-trip an alpha channel. CMYK has no alpha, so it is dropped there.
Is my color data sent anywhere?
No. Every conversion on this site runs in your browser with no network request, no account and no analytics. You can disconnect and it keeps working.