#AA370D
Closest named color: Rusty Red (#AF2F0D). oklch(50.1% 0.158 37.5), rgb(170, 55, 13).
Aa
White text reads best on this color (6.43:1).
About this color
#AA370D is a medium-dark, vivid red. In OKLCH its lightness is 50%, its chroma 0.158 and its hue 38°. Its hue sits on the warm side of the wheel. The nearest named color is Rusty Red (#AF2F0D), ΔE 0.015 away. White text reads best on it, at 6.43:1.
| Hue family | Reds |
| Lightness | medium-dark (50%) |
| Chroma | vivid (0.158) |
| Temperature | warm |
| Nearest name | Rusty Red (#AF2F0D) |
| Black text | 3.26:1 |
| White text | 6.43:1 |
Values
| HEX | #AA370D |
| RGB | rgb(170, 55, 13) |
| HSL | hsl(16, 86%, 36%) |
| OKLCH | oklch(50.1% 0.158 37.5) |
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 #AA370D | 6.43:1 | AA | Lc -86.0 | Fine for body text |
| Black text on #AA370D | 3.26:1 | AA large text | Lc 23.2 | Dividers and decoration only |
| #AA370D text on white | 6.43:1 | AA | Lc 80.9 | Fine for body text |
| #AA370D text on black | 3.26:1 | AA large text | Lc -21.0 | 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
#FCF3F1
oklch(97.1% 0.01 32.5)
-
Step 100
100
#F8E5DF
oklch(93.5% 0.022 38.3)
-
Step 200
200
#F3D0C5
oklch(88.4% 0.042 38.2)
-
Step 300
300
#EDB09E
oklch(80.9% 0.076 37.1)
-
Step 400
400
#E18468
oklch(70.7% 0.122 37.5)
-
Step 500
500
#D6613D
oklch(63.1% 0.156 37.6)
-
Step 600
600
#C24318
oklch(55.6% 0.171 37.4)
-
Step 700
700 (this color)
#AA370D
oklch(50.1% 0.158 37.5)
-
Step 800
800
#872C0D
oklch(42.6% 0.131 37.4)
-
Step 900
900
#6D2914
oklch(37.7% 0.102 37.4)
-
Step 950
950
#40190D
oklch(27% 0.065 37.7)
#AA370D 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) | #594E03 | 0.161 |
| Deuteranopia (no green cones) | #766803 | 0.144 |
| Tritanopia (no blue cones) | #BC0F30 | 0.065 |
| Achromatopsia (no color) | #5E5E5E | 0.159 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #AA370D
#AA370D
oklch(50.1% 0.158 37.5)
- #006F85
#006F85
oklch(50% 0.09 217.9)
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 #AA370D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rusty Red #AF2F0D ΔE 0.015
- Russet #A13905 ΔE 0.019
- Rust Red #AA2704 ΔE 0.024
- Brick #A03623 ΔE 0.025
- Burnt Umber #A0450E ΔE 0.031
- Rufous #AE2012 ΔE 0.033
- Firebrick #B22222 ΔE 0.038
- Brown #A52A2A ΔE 0.039
Use #AA370D 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.