#AC3740
Closest named color: Brown (#A52A2A). oklch(51% 0.152 20.1), rgb(172, 55, 64).
Aa
White text reads best on this color (6.22:1).
About this color
#AC3740 is a medium-dark, vivid red. In OKLCH its lightness is 51%, its chroma 0.152 and its hue 20°. Its hue sits on the warm side of the wheel. The nearest named color is Brown (#A52A2A), ΔE 0.034 away. White text reads best on it, at 6.22:1.
| Hue family | Reds |
| Lightness | medium-dark (51%) |
| Chroma | vivid (0.152) |
| Temperature | warm |
| Nearest name | Brown (#A52A2A) |
| Black text | 3.37:1 |
| White text | 6.22:1 |
Values
| HEX | #AC3740 |
| RGB | rgb(172, 55, 64) |
| HSL | hsl(355, 52%, 45%) |
| OKLCH | oklch(51% 0.152 20.1) |
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 #AC3740 | 6.22:1 | AA | Lc -85.2 | Fine for body text |
| Black text on #AC3740 | 3.37:1 | AA large text | Lc 24.0 | Dividers and decoration only |
| #AC3740 text on white | 6.22:1 | AA | Lc 80.0 | Fine for body text |
| #AC3740 text on black | 3.37:1 | AA large text | Lc -21.8 | 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
#FCF3F3
oklch(97.1% 0.01 17.3)
-
Step 100
100
#F8E5E4
oklch(93.7% 0.021 21.2)
-
Step 200
200
#F3CFCE
oklch(88.5% 0.041 19.8)
-
Step 300
300
#EDAEAD
oklch(80.9% 0.074 19.9)
-
Step 400
400
#E08182
oklch(70.6% 0.117 19.8)
-
Step 500
500
#D55E62
oklch(63.1% 0.15 20.4)
-
Step 600
600
#C04049
oklch(55.6% 0.163 20.3)
-
Step 700
700 (this color)
#AC3740
oklch(51% 0.152 20.1)
-
Step 800
800
#862A31
oklch(42.6% 0.125 19.9)
-
Step 900
900
#6C282B
oklch(37.7% 0.097 20.4)
-
Step 950
950
#401819
oklch(27% 0.063 20.7)
#AC3740 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) | #565140 | 0.165 |
| Deuteranopia (no green cones) | #736A3D | 0.153 |
| Tritanopia (no blue cones) | #BC1B3B | 0.040 |
| Achromatopsia (no color) | #616161 | 0.153 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #AC3740
#AC3740
oklch(51% 0.152 20.1)
- #00757A
#00757A
oklch(51.1% 0.087 200)
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 #AC3740, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Brown #A52A2A ΔE 0.034
- Firebrick #B22222 ΔE 0.036
- Dull Red #BB3F3F ΔE 0.037
- Light Burgundy #A8415B ΔE 0.037
- Light Maroon #A24857 ΔE 0.039
- Brick #A03623 ΔE 0.042
- Rusty Red #AF2F0D ΔE 0.045
- Dusty Red #B9484E ΔE 0.045
Use #AC3740 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.