#337CAE
Closest named color: Nice Blue (#107AB0). oklch(56.3% 0.106 242.1), rgb(51, 124, 174).
Aa
Black text reads best on this color (4.63:1).
About this color
#337CAE is a medium-dark, moderately saturated blue. In OKLCH its lightness is 56%, its chroma 0.106 and its hue 242°. Its hue sits on the cool side of the wheel. The nearest named color is Nice Blue (#107AB0), ΔE 0.019 away. Black text reads best on it, at 4.63:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.106) |
| Temperature | cool |
| Nearest name | Nice Blue (#107AB0) |
| Black text | 4.63:1 |
| White text | 4.53:1 |
Values
| HEX | #337CAE |
| RGB | rgb(51, 124, 174) |
| HSL | hsl(204, 55%, 44%) |
| OKLCH | oklch(56.3% 0.106 242.1) |
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 #337CAE | 4.53:1 | AA | Lc -76.7 | Fine for body text |
| Black text on #337CAE | 4.63:1 | AA | Lc 32.9 | Non-text elements, placeholder text |
| #337CAE text on white | 4.53:1 | AA | Lc 71.2 | Content text, not long reading |
| #337CAE text on black | 4.63:1 | AA | Lc -30.5 | Non-text elements, placeholder text |
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
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E2EBF2
oklch(93.5% 0.014 241)
-
Step 200
200
#CBDCE9
oklch(88.6% 0.026 240.7)
-
Step 300
300
#A6C5DD
oklch(80.9% 0.048 241.5)
-
Step 400
400
#76A7CC
oklch(70.7% 0.075 241.7)
-
Step 500
500
#5090BF
oklch(63% 0.097 242.3)
-
Step 600
600 (this color)
#337CAE
oklch(56.3% 0.106 242.1)
-
Step 700
700
#226693
oklch(49% 0.098 242.1)
-
Step 800
800
#1F5478
oklch(42.8% 0.082 242)
-
Step 900
900
#1F4560
oklch(37.6% 0.063 242.1)
-
Step 950
950
#132938
oklch(27% 0.04 240.2)
#337CAE 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) | #657DB0 | 0.052 |
| Deuteranopia (no green cones) | #5471AD | 0.041 |
| Tritanopia (no blue cones) | #00888D | 0.075 |
| Achromatopsia (no color) | #767676 | 0.106 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #337CAE
#337CAE
oklch(56.3% 0.106 242.1)
- #A1662B
#A1662B
oklch(56.4% 0.106 62.4)
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 #337CAE, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Nice Blue #107AB0 ΔE 0.019
- Flat Blue #3C73A8 ΔE 0.025
- Steel Blue #4682B4 ΔE 0.026
- Cerulean #457B9D ΔE 0.029
- Windows Blue #3778BF ΔE 0.032
- Dull Blue #49759C ΔE 0.033
- Cool Blue #4984B8 ΔE 0.034
- Muted Blue #3B719F ΔE 0.034
Use #337CAE 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.