#C43B03
Closest named color: Sinopia (#BB3E03). oklch(55% 0.182 37.2), rgb(196, 59, 3).
Aa
White text reads best on this color (5.28:1).
About this color
#C43B03 is a medium-dark, vivid red. In OKLCH its lightness is 55%, its chroma 0.182 and its hue 37°. Its hue sits on the warm side of the wheel. The nearest named color is Sinopia (#BB3E03), ΔE 0.018 away. White text reads best on it, at 5.28:1.
| Hue family | Reds |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.182) |
| Temperature | warm |
| Nearest name | Sinopia (#BB3E03) |
| Black text | 3.97:1 |
| White text | 5.28:1 |
Values
| HEX | #C43B03 |
| RGB | rgb(196, 59, 3) |
| HSL | hsl(17, 97%, 39%) |
| OKLCH | oklch(55% 0.182 37.2) |
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 #C43B03 | 5.28:1 | AA | Lc -80.4 | Fine for body text |
| Black text on #C43B03 | 3.97:1 | AA large text | Lc 29.1 | Dividers and decoration only |
| #C43B03 text on white | 5.28:1 | AA | Lc 75.0 | Content text, not long reading |
| #C43B03 text on black | 3.97:1 | AA large text | Lc -26.7 | 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 600.
-
Step 50
50
#FDF3F0
oklch(97.1% 0.012 37.4)
-
Step 100
100
#F9E5DF
oklch(93.6% 0.023 37.4)
-
Step 200
200
#F5CFC4
oklch(88.4% 0.046 36.7)
-
Step 300
300
#F0AF9B
oklch(81% 0.082 37.8)
-
Step 400
400
#E58164
oklch(70.6% 0.131 37)
-
Step 500
500
#DB5D37
oklch(63.2% 0.167 37.2)
-
Step 600
600 (this color)
#C43B03
oklch(55% 0.182 37.2)
-
Step 700
700
#A93100
oklch(49.2% 0.163 37.3)
-
Step 800
800
#8B2803
oklch(42.8% 0.14 37.2)
-
Step 900
900
#702710
oklch(37.9% 0.109 37.3)
-
Step 950
950
#42180B
oklch(27.1% 0.069 37.6)
#C43B03 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) | #655800 | 0.185 |
| Deuteranopia (no green cones) | #867700 | 0.167 |
| Tritanopia (no blue cones) | #D80033 | 0.071 |
| Achromatopsia (no color) | #6C6C6C | 0.183 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #C43B03
#C43B03
oklch(55% 0.182 37.2)
- #007F97
#007F97
oklch(55% 0.098 217.2)
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 #C43B03, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sinopia #BB3E03 ΔE 0.018
- Brick Orange #C14A09 ΔE 0.025
- Burnt Orange #C04E01 ΔE 0.034
- Dull Red #BB3F3F ΔE 0.045
- Burnt Siena #B75203 ΔE 0.046
- Rust Orange #C45508 ΔE 0.048
- Rusty Red #AF2F0D ΔE 0.051
- Cinnamon #AC4F06 ΔE 0.054
Use #C43B03 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.