#AC1B37
Closest named color: Rouge (#AB1239). oklch(48.4% 0.177 17.7), rgb(172, 27, 55).
Aa
White text reads best on this color (7.08:1).
About this color
#AC1B37 is a medium-dark, vivid red. In OKLCH its lightness is 48%, its chroma 0.177 and its hue 18°. Its hue sits on the warm side of the wheel. The nearest named color is Rouge (#AB1239), ΔE 0.010 away. White text reads best on it, at 7.08:1.
| Hue family | Reds |
| Lightness | medium-dark (48%) |
| Chroma | vivid (0.177) |
| Temperature | warm |
| Nearest name | Rouge (#AB1239) |
| Black text | 2.96:1 |
| White text | 7.08:1 |
Values
| HEX | #AC1B37 |
| RGB | rgb(172, 27, 55) |
| HSL | hsl(348, 73%, 39%) |
| OKLCH | oklch(48.4% 0.177 17.7) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #AC1B37 | 7.08:1 | AAA | Lc -87.9 | Fine for body text |
| Black text on #AC1B37 | 2.96:1 | Fails | Lc 21.2 | Dividers and decoration only |
| #AC1B37 text on white | 7.08:1 | AAA | Lc 82.8 | Fine for body text |
| #AC1B37 text on black | 2.96:1 | Fails | Lc -19.1 | Dividers and decoration only |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 700.
-
Step 50
50
#FDF3F2
oklch(97.2% 0.011 24.3)
-
Step 100
100
#FAE4E4
oklch(93.7% 0.024 17.6)
-
Step 200
200
#F7CDCD
oklch(88.4% 0.048 18.1)
-
Step 300
300
#F3AAAC
oklch(80.8% 0.086 17.3)
-
Step 400
400
#E97A80
oklch(70.6% 0.137 17.8)
-
Step 500
500
#DF5261
oklch(63.1% 0.176 17.5)
-
Step 600
600
#CA2F47
oklch(55.6% 0.19 17.9)
-
Step 700
700 (this color)
#AC1B37
oklch(48.4% 0.177 17.7)
-
Step 800
800
#8E1D2F
oklch(42.7% 0.147 17.9)
-
Step 900
900
#72202A
oklch(37.7% 0.114 17.7)
-
Step 950
950
#431419
oklch(26.9% 0.073 17.1)
#AC1B37 with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #494537 | 0.197 |
| Deuteranopia (no green cones) | #6D6333 | 0.179 |
| Tritanopia (no blue cones) | #BD0028 | 0.036 |
| Achromatopsia (no color) | #585858 | 0.179 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #AC1B37
#AC1B37
oklch(48.4% 0.177 17.7)
- #006D6F
#006D6F
oklch(48.5% 0.083 197)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #AC1B37, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rouge #AB1239 ΔE 0.010
- Brown #A52A2A ΔE 0.029
- Firebrick #B22222 ΔE 0.031
- Raspberry #B00149 ΔE 0.034
- Rose Red #BE013C ΔE 0.037
- Rufous #AE2012 ΔE 0.039
- Lipstick Red #C0022F ΔE 0.040
- Auburn #9B2226 ΔE 0.041
Use #AC1B37 in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.