Inspect DarkGreen (#006400) in HEX, RGB, HSL, LCH and OKLCH, check its contrast, and copy the value you need.
DarkGreen
#006400
White text reads best on this background, at 7.44:1.
DarkGreen is one of the 148 CSS named colors, and resolves to #006400 in every browser. In numbers that is rgb(0, 100, 0) and hsl(120, 100%, 20%). Perceptually it is a dark, moderately saturated color: OKLCH puts its lightness at 44% and its chroma at 0.148. It sits in the greens at 142 degrees of OKLCH hue, and reads as a cool color.
White text clears WCAG AA on a DarkGreen background at 7.44:1, and AAA as well. That combination of lightness and chroma makes it a workable mid-tone, the kind of value that lands in the middle of a shade scale.
The closest CSS named colors to DarkGreen, measured with CIEDE2000, are Green (#008000), DarkOliveGreen (#556B2F), ForestGreen (#228B22). If DarkGreen is not quite right, those are the nearest keywords to try before reaching for a custom value.
HEX
#006400
RGB
rgb(0, 100, 0)
HSL
hsl(120, 100%, 20%)
HWB
hwb(120 0% 61%)
CMYK
cmyk(100%, 0%, 100%, 61%)
LAB
lab(36.24 -39.89 40.76)
LCH
lch(36.24 57.03 134.38)
OKLCH
oklch(43.6% 0.1484 142.5)
WCAG asks for 4.5:1 between body text and its background. On #006400 white text measures 7.44:1 and black text 2.82:1, so white clears it and black does not.
White text on DarkGreen
WCAG 2.2
7.44:1
APCA
Lc 90
Passes AA body text
Passes AAA body text
Passes AA large text
Black text on DarkGreen
WCAG 2.2
2.82:1
APCA
Lc 18
Fails AA body text
Fails AAA body text
Fails AA large text
Check DarkGreen against any other color in the contrast checker.
DarkGreen sits at 44% OKLCH lightness. Holding its hue and chroma and moving only that value carries it up to #ECFFE9 and down to #000900, which keeps the family recognizable instead of letting it drift toward gray the way a plain HSL ramp does.
#31852C
20% lighter
#54A64E
40% lighter
#76C970
60% lighter
#99ED92
80% lighter
#ECFFE9
100% lighter
#005000
20% darker
#003C00
40% darker
#002A00
60% darker
#001900
80% darker
#000900
100% darker
Build a full accessible scale from #006400 in the shade generator.
Hues rotated around #006400 in OKLCH, then pulled back into the sRGB gamut. Each swatch is labelled with the nearest CSS named color so you have a keyword to start from.
DarkGreen sits at 142 degrees. Rotating it a half turn lands on 322 degrees, the hue directly opposite. It is the strongest pairing you can make without changing lightness, and the one most likely to vibrate if you use both at full chroma.
The neighbors of DarkGreen at 112 and 172 degrees. They stay close enough to read as the same family, which is what you want for hover states, secondary surfaces and gradients.
142, 262 and 22 degrees divide the wheel into thirds. Balanced enough to carry a whole palette without one color dominating the other two.
Instead of the complement at 322 degrees, this pair flanks it at 292 and 352. You keep most of the contrast of a complementary pairing while losing the harshness.
Explore more combinations around DarkGreen on the color wheel.
The biggest shift is under protanopia, where #006400 reads as #694F00, 26.7 CIEDE2000 units away. If DarkGreen is the only thing marking a state or a series, roughly one viewer in twelve will miss it.
Protanopia
#694F00
Deuteranopia
#564304
Tritanopia
#005D45
Achromatopsia
#474847
The nearest CSS keywords to #006400, ranked by perceptual distance rather than by how close their hex digits happen to look.