#C51021
Closest named color: Scarlet (#BE0119). oklch(52.3% 0.206 25.5), rgb(197, 16, 33).
Aa
White text reads best on this color (6.05:1).
About this color
#C51021 is a medium-dark, vivid red. In OKLCH its lightness is 52%, its chroma 0.206 and its hue 25°. Its hue sits on the warm side of the wheel. The nearest named color is Scarlet (#BE0119), ΔE 0.019 away. White text reads best on it, at 6.05:1.
| Hue family | Reds |
| Lightness | medium-dark (52%) |
| Chroma | vivid (0.206) |
| Temperature | warm |
| Nearest name | Scarlet (#BE0119) |
| Black text | 3.47:1 |
| White text | 6.05:1 |
Values
| HEX | #C51021 |
| RGB | rgb(197, 16, 33) |
| HSL | hsl(354, 85%, 42%) |
| OKLCH | oklch(52.3% 0.206 25.5) |
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 #C51021 | 6.05:1 | AA | Lc -83.2 | Fine for body text |
| Black text on #C51021 | 3.47:1 | AA large text | Lc 26.2 | Dividers and decoration only |
| #C51021 text on white | 6.05:1 | AA | Lc 77.9 | Fine for body text |
| #C51021 text on black | 3.47:1 | AA large text | Lc -23.9 | 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
#FDE3E0
oklch(93.6% 0.029 25.6)
-
Step 200
200
#FCCCC7
oklch(88.6% 0.055 25.2)
-
Step 300
300
#FBA7A0
oklch(80.9% 0.101 24.8)
-
Step 400
400
#F4736C
oklch(70.7% 0.16 25.1)
-
Step 500
500
#EB4544
oklch(63.1% 0.203 25.4)
-
Step 600
600
#D70D23
oklch(55.7% 0.222 25.6)
-
Step 700
700 (this color)
#C51021
oklch(52.3% 0.206 25.5)
-
Step 800
800
#970515
oklch(42.8% 0.171 25.5)
-
Step 900
900
#791618
oklch(37.7% 0.133 25.6)
-
Step 950
950
#47100F
oklch(26.9% 0.084 25.7)
#C51021 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) | #534B1F | 0.227 |
| Deuteranopia (no green cones) | #7D7017 | 0.206 |
| Tritanopia (no blue cones) | #DA001B | 0.042 |
| Achromatopsia (no color) | #636363 | 0.207 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #C51021
#C51021
oklch(52.3% 0.206 25.5)
- #007883
#007883
oklch(52.3% 0.089 206)
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 #C51021, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Scarlet #BE0119 ΔE 0.019
- Lipstick Red #C0022F ΔE 0.021
- Cherry #CF0234 ΔE 0.028
- Rose Red #BE013C ΔE 0.037
- Firebrick #B22222 ΔE 0.037
- Ruby #CA0147 ΔE 0.046
- Rufous #AE2012 ΔE 0.048
- Dull Red #BB3F3F ΔE 0.051
Use #C51021 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.