#B03B00
Closest named color: Rusty Red (#AF2F0D). oklch(51.5% 0.162 39.9), rgb(176, 59, 0).
Aa
White text reads best on this color (6.04:1).
About this color
#B03B00 is a medium-dark, vivid red. In OKLCH its lightness is 52%, its chroma 0.162 and its hue 40°. Its hue sits on the warm side of the wheel. The nearest named color is Rusty Red (#AF2F0D), ΔE 0.023 away. White text reads best on it, at 6.04:1.
| Hue family | Reds |
| Lightness | medium-dark (52%) |
| Chroma | vivid (0.162) |
| Temperature | warm |
| Nearest name | Rusty Red (#AF2F0D) |
| Black text | 3.47:1 |
| White text | 6.04:1 |
Values
| HEX | #B03B00 |
| RGB | rgb(176, 59, 0) |
| HSL | hsl(20, 100%, 35%) |
| OKLCH | oklch(51.5% 0.162 39.9) |
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 #B03B00 | 6.04:1 | AA | Lc -84.4 | Fine for body text |
| Black text on #B03B00 | 3.47:1 | AA large text | Lc 24.9 | Dividers and decoration only |
| #B03B00 text on white | 6.04:1 | AA | Lc 79.1 | Fine for body text |
| #B03B00 text on black | 3.47:1 | AA large text | Lc -22.7 | 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 700.
-
Step 50
50
#FCF3F0
oklch(97% 0.011 39.4)
-
Step 100
100
#F8E5DF
oklch(93.5% 0.022 38.3)
-
Step 200
200
#F4D0C4
oklch(88.5% 0.044 39.3)
-
Step 300
300
#EEB09B
oklch(81% 0.079 39.5)
-
Step 400
400
#E28463
oklch(70.7% 0.125 40)
-
Step 500
500
#D76135
oklch(63.1% 0.16 40)
-
Step 600
600
#C34301
oklch(55.7% 0.174 40)
-
Step 700
700 (this color)
#B03B00
oklch(51.5% 0.162 39.9)
-
Step 800
800
#882C00
oklch(42.7% 0.134 40.1)
-
Step 900
900
#6E290E
oklch(37.8% 0.105 39.9)
-
Step 950
950
#40190B
oklch(26.9% 0.065 39.7)
#B03B00 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) | #5E5200 | 0.161 |
| Deuteranopia (no green cones) | #7B6C00 | 0.144 |
| Tritanopia (no blue cones) | #C21332 | 0.071 |
| Achromatopsia (no color) | #636363 | 0.163 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #B03B00
#B03B00
oklch(51.5% 0.162 39.9)
- #00748D
#00748D
oklch(51.7% 0.094 219.7)
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 #B03B00, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rusty Red #AF2F0D ΔE 0.023
- Sinopia #BB3E03 ΔE 0.024
- Russet #A13905 ΔE 0.031
- Burnt Umber #A0450E ΔE 0.033
- Rust Red #AA2704 ΔE 0.037
- Cinnamon #AC4F06 ΔE 0.039
- Brick #A03623 ΔE 0.041
- Rufous #AE2012 ΔE 0.044
Use #B03B00 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.