#337DE3
Closest named color: Clear Blue (#247AFD). oklch(59.7% 0.171 257.4), rgb(51, 125, 227).
Aa
Black text reads best on this color (5.18:1).
About this color
#337DE3 is a medium-dark, vivid blue. In OKLCH its lightness is 60%, its chroma 0.171 and its hue 257°. Its hue sits on the cool side of the wheel. The nearest named color is Clear Blue (#247AFD), ΔE 0.041 away. Black text reads best on it, at 5.18:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | vivid (0.171) |
| Temperature | cool |
| Nearest name | Clear Blue (#247AFD) |
| Black text | 5.18:1 |
| White text | 4.05:1 |
Values
| HEX | #337DE3 |
| RGB | rgb(51, 125, 227) |
| HSL | hsl(215, 76%, 55%) |
| OKLCH | oklch(59.7% 0.171 257.4) |
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 #337DE3 | 4.05:1 | AA large text | Lc -72.8 | Content text, not long reading |
| Black text on #337DE3 | 5.18:1 | AA | Lc 36.8 | Non-text elements, placeholder text |
| #337DE3 text on white | 4.05:1 | AA large text | Lc 67.3 | Content text, not long reading |
| #337DE3 text on black | 5.18:1 | AA | Lc -34.4 | 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 500.
-
Step 50
50
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E0EBFA
oklch(93.6% 0.024 256.1)
-
Step 200
200
#C6DBF8
oklch(88.5% 0.046 256.5)
-
Step 300
300
#9FC3F7
oklch(81% 0.084 257.5)
-
Step 400
400
#69A2F3
oklch(70.8% 0.134 257.3)
-
Step 500
500 (this color)
#337DE3
oklch(59.7% 0.171 257.4)
-
Step 600
600
#186FDD
oklch(55.7% 0.186 257.3)
-
Step 700
700
#075CC0
oklch(49.2% 0.173 257.4)
-
Step 800
800
#0D4C9B
oklch(42.8% 0.142 257.3)
-
Step 900
900
#14407B
oklch(37.7% 0.111 257.2)
-
Step 950
950
#0D2648
oklch(27% 0.07 257)
#337DE3 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) | #4787E7 | 0.033 |
| Deuteranopia (no green cones) | #1F77E1 | 0.021 |
| Tritanopia (no blue cones) | #0095A5 | 0.131 |
| Achromatopsia (no color) | #7E7E7E | 0.171 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #337DE3
#337DE3
oklch(59.7% 0.171 257.4)
- #A87400
#A87400
oklch(59.7% 0.125 77.5)
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 #337DE3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Clear Blue #247AFD ΔE 0.041
- Dark Sky Blue #448EE4 ΔE 0.050
- Royal Blue #4169E1 ΔE 0.050
- Water Blue #0E87CC ΔE 0.050
- Cerulean Blue #056EEE ΔE 0.050
- Windows Blue #3778BF ΔE 0.055
- Soft Blue #6488EA ΔE 0.059
- Dodger Blue #1E90FF ΔE 0.059
Use #337DE3 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.