#B40523
Closest named color: Firebrick (#B22222). oklch(48.7% 0.195 23.4), rgb(180, 5, 35).
Aa
White text reads best on this color (7.03:1).
About this color
#B40523 is a medium-dark, vivid red. In OKLCH its lightness is 49%, its chroma 0.195 and its hue 23°. Its hue sits on the warm side of the wheel. The nearest named color is Firebrick (#B22222), ΔE 0.021 away. White text reads best on it, at 7.03:1.
| Hue family | Reds |
| Lightness | medium-dark (49%) |
| Chroma | vivid (0.195) |
| Temperature | warm |
| Nearest name | Firebrick (#B22222) |
| Black text | 2.98:1 |
| White text | 7.03:1 |
Values
| HEX | #B40523 |
| RGB | rgb(180, 5, 35) |
| HSL | hsl(350, 95%, 36%) |
| OKLCH | oklch(48.7% 0.195 23.4) |
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 #B40523 | 7.03:1 | AAA | Lc -87.0 | Fine for body text |
| Black text on #B40523 | 2.98:1 | Fails | Lc 22.2 | Dividers and decoration only |
| #B40523 text on white | 7.03:1 | AAA | Lc 81.9 | Fine for body text |
| #B40523 text on black | 2.98:1 | Fails | Lc -20.0 | 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
#FEF2F1
oklch(97% 0.013 23.2)
-
Step 100
100
#FCE3E1
oklch(93.6% 0.028 23.2)
-
Step 200
200
#FACCC9
oklch(88.4% 0.052 22.6)
-
Step 300
300
#F8A9A4
oklch(81% 0.094 23.4)
-
Step 400
400
#F07673
oklch(70.7% 0.151 23.1)
-
Step 500
500
#E74A4E
oklch(63.1% 0.193 23.3)
-
Step 600
600
#D21F31
oklch(55.6% 0.209 23.5)
-
Step 700
700 (this color)
#B40523
oklch(48.7% 0.195 23.4)
-
Step 800
800
#93121F
oklch(42.7% 0.161 23.5)
-
Step 900
900
#761B1F
oklch(37.7% 0.125 23.4)
-
Step 950
950
#461213
oklch(27.1% 0.08 23.1)
#B40523 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) | #4A4222 | 0.215 |
| Deuteranopia (no green cones) | #71651B | 0.196 |
| Tritanopia (no blue cones) | #C70017 | 0.041 |
| Achromatopsia (no color) | #595959 | 0.196 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #B40523
#B40523
oklch(48.7% 0.195 23.4)
- #006D75
#006D75
oklch(48.7% 0.083 203.7)
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 #B40523, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Firebrick #B22222 ΔE 0.021
- Scarlet #BE0119 ΔE 0.022
- Rufous #AE2012 ΔE 0.027
- Lipstick Red #C0022F ΔE 0.028
- Rouge #AB1239 ΔE 0.030
- Rose Red #BE013C ΔE 0.035
- Brown #A52A2A ΔE 0.036
- Rust Red #AA2704 ΔE 0.041
Use #B40523 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.