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npm · #1040 most downloaded on npm
Parse CSS color values
Last release 3 days ago
02 Oct 2026
Ships fairly regularly
a new release about every 3 weeks
Nearly every release is documented
notes for 59 of 59 stable releases
Nothing withdrawn
no release was ever pulled
4 years old
59 releases · first in 2023
One column per quarter.
Updated `@csstools/css-calc` to `3.4.3` (patch)
October 2, 2026
@csstools/css-calc to 3.4.3 (patch)Updated `@csstools/css-parser-algorithms` to `4.0.2` (patch)
October 1, 2026
@csstools/css-parser-algorithms to 4.0.2 (patch)@csstools/css-calc to 3.4.2 (patch)Updated `@csstools/css-tokenizer` to `4.0.1` (patch)
September 25, 2026
@csstools/css-tokenizer to 4.0.1 (patch)@csstools/color-helpers to 6.1.2 (patch)@csstools/css-tokenizer to 4.0.2 (patch)@csstools/css-parser-algorithms to 4.0.1 (patch)@csstools/css-calc to 3.4.1 (patch)Updated `@csstools/css-calc` to `3.4.0` (minor)
September 13, 2026
@csstools/css-calc to 3.4.0 (minor)Normalize hue in computedValue()
August 30, 2026
computedValue()Preserve powerless hue in color-mix() when the input color space equals the interpolation color space, matching relative color syntax.
August 25, 2026
color-mix() when the input color space equals the interpolation color space, matching relative color syntax.Add computedValue() serialization function for color data.
August 15, 2026
computedValue() serialization function for color data.alpha in the relative alpha() function.@csstools/color-helpers to 6.1.1 (patch)Fix handling of none in some edge cases
July 22, 2026
none in some edge cases@csstools/css-calc to 3.3.0 (minor)Skip whitepoint conversion when it isn't needed during color conversion
June 25, 2026
@csstools/color-helpers to 6.1.0 (minor)Add color-mix syntax flag to mix notations with only a single value (e.g. color-mix(in oklch, red))
June 19, 2026
color-mix syntax flag to mix notations with only a single value (e.g. color-mix(in oklch, red))Fix normalization of hue to [0, 360] range when hue is not finite
June 14, 2026
hue to [0, 360] range when hue is not finiteFix normalization of hue to [0, 360] range when hue is a negative number
June 14, 2026
hue to [0, 360] range when hue is a negative numberFix handling of hue in interpolation when both parts have a missing hue component
June 14, 2026
hue in interpolation when both parts have a missing hue component_June 13, 2026_ - Fix none alpha in alpha()
June 13, 2026
none alpha in alpha()Assign rgb color notation to contrast-color() (instead of srgb).
June 10, 2026
rgb color notation to contrast-color() (instead of srgb).Remove special handling of all zero percentages in color-mix()
June 10, 2026
color-mix()Fix analogous components and sets for hwb()
May 13, 2026
hwb()@csstools/css-calc to 3.2.1 (patch)Add support for analogous set in color interpolations
April 12, 2026
@csstools/css-calc to 3.2.0 (minor)Updated `@csstools/css-calc` to `3.1.1` (minor)
February 21, 2026
@csstools/css-calc to 3.1.1 (minor)@csstools/color-helpers to 6.0.2 (patch)Updated `@csstools/color-helpers` to `6.0.1` (patch)
January 25, 2026
@csstools/color-helpers to 6.0.1 (patch)Updated: Support for Node 20.19.0 or later (major).
January 14, 2026
20.19.0 or later (major).commonjs API. In supported Node versions require(esm) will work without needing to make code changes.@csstools/color-helpers to 6.0.0 (major)@csstools/css-tokenizer to 4.0.0 (major)@csstools/css-parser-algorithms to 4.0.0 (major)@csstools/css-calc to 3.0.0 (major)Add support for display-p3-linear in color(display-p3-linear 0.3081 0.014 0.0567)
August 22, 2025
display-p3-linear in color(display-p3-linear 0.3081 0.014 0.0567)display-p3-linear in color-mix(in display-p3-linear, red, blue)color-mix(red, blue)alpha(from red / 0.5)@csstools/color-helpers to 5.1.0 (minor)Updated `@csstools/css-tokenizer` to `3.0.4` (patch)
May 27, 2025
@csstools/css-tokenizer to 3.0.4 (patch)@csstools/css-parser-algorithms to 3.0.5 (patch)@csstools/css-calc to 2.1.4 (patch)Drop the max keyword for contrast-color( )
April 19, 2025
max keyword for contrast-color( <color> )@csstools/css-calc to 2.1.3 (patch)Use Number.isNaN instead of NaN for consistency.
February 23, 2025
Number.isNaN instead of NaN for consistency.@csstools/color-helpers to 5.0.2 (patch)@csstools/css-calc to 2.1.2 (patch)Fix precision of negative numbers.
December 27, 2024
@csstools/css-calc to 2.1.1 (patch)Updated `@csstools/css-calc` to `2.1.0` (minor)
November 11, 2024
@csstools/css-calc to 2.1.0 (minor)Updated `@csstools/css-tokenizer` to `3.0.3` (patch)
November 1, 2024
@csstools/css-tokenizer to 3.0.3 (patch)@csstools/css-parser-algorithms to 3.0.4 (patch)@csstools/css-calc to 2.0.4 (patch)Updated `@csstools/css-parser-algorithms` to `3.0.3` (patch)
October 23, 2024
@csstools/css-parser-algorithms to 3.0.3 (patch)@csstools/css-calc to 2.0.3 (patch)Updated `@csstools/css-tokenizer` to `3.0.2` (patch)
October 10, 2024
@csstools/css-tokenizer to 3.0.2 (patch)@csstools/css-parser-algorithms to 3.0.2 (patch)@csstools/css-calc to 2.0.2 (patch)Updated `@csstools/css-tokenizer` to `3.0.1` (patch)
August 18, 2024
@csstools/css-tokenizer to 3.0.1 (patch)@csstools/css-parser-algorithms to 3.0.1 (patch)@csstools/css-calc to 2.0.1 (patch)Updated `@csstools/color-helpers` to `5.0.1` (patch)
August 14, 2024
@csstools/color-helpers to 5.0.1 (patch)Updated: Support for Node v18+ (major).
August 3, 2024
@csstools/css-tokenizer to 3.0.0 (major)@csstools/css-parser-algorithms to 3.0.0 (major)@csstools/css-calc to 2.0.0 (major)fix serializeP3 when gamutMapping is false
July 13, 2024
serializeP3 when gamutMapping is falseUpdated `@csstools/css-tokenizer` to `2.4.1` (patch)
July 6, 2024
@csstools/css-tokenizer to 2.4.1 (patch)@csstools/css-parser-algorithms to 2.7.1 (patch)@csstools/css-calc to 1.2.4 (patch)Updated `@csstools/color-helpers` to `4.2.1` (patch)
June 29, 2024
@csstools/color-helpers to 4.2.1 (patch)@csstools/css-tokenizer to 2.3.2 (patch)@csstools/css-parser-algorithms to 2.7.0 (minor)@csstools/css-calc to 1.2.3 (patch)Updated `@csstools/css-tokenizer` to `2.3.1` (patch)
May 4, 2024
@csstools/css-tokenizer to 2.3.1 (patch)@csstools/css-parser-algorithms to 2.6.3 (patch)@csstools/css-calc to 1.2.2 (patch)Improve handling of NaN and Infinity in color functions.
May 4, 2024
NaN and Infinity in color functions.@csstools/css-tokenizer to 2.3.0 (minor)@csstools/css-parser-algorithms to 2.6.2 (patch)@csstools/css-calc to 1.2.1 (patch)Switch to the ray-tracing gamut mapping algorithm. This is a minimally invasive change when generating fallback colors for CSS but breaking if you rel
April 21, 2024
none keyword conversion in relative color syntax origin values. (again)@csstools/color-helpers to 4.2.0 (minor)Fix missing rectangular color spaces for interpolation in color-mix().
March 31, 2024
color-mix().none keyword conversion in relative color syntax origin values.@csstools/color-helpers to 4.1.0 (minor)Fix powerless components for lch and oklch with none chroma.
March 16, 2024
lch and oklch with none chroma.Fix powerless components for hsl with none saturation.
March 16, 2024
hsl with none saturation.Add support for contrast-color( max )
March 13, 2024
contrast-color( <color> max )rgba and hsla color notations.@csstools/css-tokenizer to 2.2.4 (patch)@csstools/css-parser-algorithms to 2.6.1 (patch)@csstools/css-calc to 1.2.0 (minor)Clamp negative saturation to zero in modern hsl
February 19, 2024
hsl@csstools/css-parser-algorithms to 2.6.0 (minor)@csstools/css-calc to 1.1.7 (patch)Updated `@csstools/css-tokenizer` to `2.2.3` (patch)
December 31, 2023
@csstools/css-tokenizer to 2.2.3 (patch)@csstools/css-parser-algorithms to 2.5.0 (minor)@csstools/css-calc to 1.1.6 (patch)Add the Experimental syntax flag, to be used in future features.
December 15, 2023
Experimental syntax flag, to be used in future features.serializeHSL function.@csstools/color-helpers to 4.0.0 (major)@csstools/css-tokenizer to 2.2.2 (patch)@csstools/css-parser-algorithms to 2.4.0 (minor)@csstools/css-calc to 1.1.5 (patch)Add utility to determine if a color is in the Display P3 gamut.
October 9, 2023
Fix interpolation of hue when either or both components are none and longer is the interpolation method.
October 2, 2023
hue when either or both components are none and longer is the interpolation method.Updated `@csstools/css-tokenizer` to `2.2.1` (patch)
September 24, 2023
@csstools/css-tokenizer to 2.2.1 (patch)@csstools/css-parser-algorithms to 2.3.2 (patch)@csstools/css-calc to 1.1.4 (patch)Fix clipping of values in hsl, hwb and rgb color notations.
September 2, 2023
hsl, hwb and rgb color notations.@csstools/color-helpers to 3.0.2 (patch)Always convert to the target color space, even when the input color is already in that specific color space.
August 28, 2023
serializeOKLCH function.@csstools/color-helpers to 3.0.1 (patch)Fix value calculation for s, l (hsl) and w, b (hwb) components in relative color syntax.
July 24, 2023
hwb.s, l (hsl) and w, b (hwb) components in relative color syntax.a and b components in lab and oklab are analogous.hue unless otherwise specified.@csstools/css-tokenizer to 2.2.0 (minor)@csstools/css-parser-algorithms to 2.3.1 (patch)@csstools/css-calc to 1.1.3 (patch)Updated `@csstools/color-helpers` to `3.0.0` (major)
July 3, 2023
@csstools/color-helpers to 3.0.0 (major)@csstools/css-parser-algorithms to 2.3.0 (minor)@csstools/css-calc to 1.1.2 (patch)Fix value calculation for hue components in relative color syntax.
June 14, 2023
hue components in relative color syntax.Add support for relative color syntax.
May 19, 2023
@csstools/color-helpers to 2.1.0 (minor)Updated @csstools/css-tokenizer to 2.1.1 (patch)
April 10, 2023
@csstools/css-tokenizer to 2.1.1 (patch)@csstools/css-parser-algorithms to 2.1.1 (patch)@csstools/css-calc to 1.1.1 (patch)Improve the detection of math function in color notations.
April 10, 2023
Add a flag to serializeP3 and serializeRGB to skip gamut mapping.
March 28, 2023
serializeP3 and serializeRGB to skip gamut mapping._March 25, 2023_ - Initial version
March 25, 2023
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