#B33A10
Closest named color: Sinopia (#BB3E03). oklch(52% 0.164 37.1), rgb(179, 58, 16).
Aa
White text reads best on this color (5.94:1).
About this color
#B33A10 is a medium-dark, vivid red. In OKLCH its lightness is 52%, its chroma 0.164 and its hue 37°. Its hue sits on the warm side of the wheel. The nearest named color is Sinopia (#BB3E03), ΔE 0.020 away. White text reads best on it, at 5.94:1.
| Hue family | Reds |
| Lightness | medium-dark (52%) |
| Chroma | vivid (0.164) |
| Temperature | warm |
| Nearest name | Sinopia (#BB3E03) |
| Black text | 3.52:1 |
| White text | 5.94:1 |
Values
| HEX | #B33A10 |
| RGB | rgb(179, 58, 16) |
| HSL | hsl(15, 84%, 38%) |
| OKLCH | oklch(52% 0.164 37.1) |
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 #B33A10 | 5.94:1 | AA | Lc -83.9 | Fine for body text |
| Black text on #B33A10 | 3.52:1 | AA large text | Lc 25.4 | Dividers and decoration only |
| #B33A10 text on white | 5.94:1 | AA | Lc 78.6 | Fine for body text |
| #B33A10 text on black | 3.52:1 | AA large text | Lc -23.1 | 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
#F9E5DF
oklch(93.6% 0.023 37.4)
-
Step 200
200
#F4D0C5
oklch(88.5% 0.043 37.7)
-
Step 300
300
#EFAF9C
oklch(80.9% 0.08 37.2)
-
Step 400
400
#E48266
oklch(70.7% 0.128 36.8)
-
Step 500
500
#D95E3A
oklch(63.1% 0.163 36.9)
-
Step 600
600
#C44011
oklch(55.6% 0.176 37.3)
-
Step 700
700 (this color)
#B33A10
oklch(52% 0.164 37.1)
-
Step 800
800
#892A08
oklch(42.7% 0.135 37.3)
-
Step 900
900
#6E2812
oklch(37.7% 0.105 37.4)
-
Step 950
950
#41180C
oklch(26.9% 0.067 37)
#B33A10 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) | #5E5205 | 0.167 |
| Deuteranopia (no green cones) | #7C6E05 | 0.152 |
| Tritanopia (no blue cones) | #C60F33 | 0.068 |
| Achromatopsia (no color) | #646464 | 0.165 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #B33A10
#B33A10
oklch(52% 0.164 37.1)
- #00758C
#00758C
oklch(51.9% 0.093 217.8)
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 #B33A10, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sinopia #BB3E03 ΔE 0.020
- Rusty Red #AF2F0D ΔE 0.021
- Russet #A13905 ΔE 0.038
- Rust Red #AA2704 ΔE 0.038
- Burnt Umber #A0450E ΔE 0.040
- Firebrick #B22222 ΔE 0.042
- Rufous #AE2012 ΔE 0.042
- Brick #A03623 ΔE 0.043
Use #B33A10 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.