#337CE7
Closest named color: Clear Blue (#247AFD). oklch(59.8% 0.178 258.4), rgb(51, 124, 231).
Aa
Black text reads best on this color (5.17:1).
About this color
#337CE7 is a medium-dark, vivid blue. In OKLCH its lightness is 60%, its chroma 0.178 and its hue 258°. Its hue sits on the cool side of the wheel. The nearest named color is Clear Blue (#247AFD), ΔE 0.035 away. Black text reads best on it, at 5.17:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | vivid (0.178) |
| Temperature | cool |
| Nearest name | Clear Blue (#247AFD) |
| Black text | 5.17:1 |
| White text | 4.05:1 |
Values
| HEX | #337CE7 |
| RGB | rgb(51, 124, 231) |
| HSL | hsl(216, 79%, 55%) |
| OKLCH | oklch(59.8% 0.178 258.4) |
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 #337CE7 | 4.05:1 | AA large text | Lc -72.8 | Content text, not long reading |
| Black text on #337CE7 | 5.17:1 | AA | Lc 36.8 | Non-text elements, placeholder text |
| #337CE7 text on white | 4.05:1 | AA large text | Lc 67.3 | Content text, not long reading |
| #337CE7 text on black | 5.17:1 | 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
#E0EBFB
oklch(93.7% 0.025 257.6)
-
Step 200
200
#C6DBFA
oklch(88.6% 0.048 258)
-
Step 300
300
#9EC3F9
oklch(81% 0.087 257.7)
-
Step 400
400
#68A1F6
oklch(70.7% 0.139 258.2)
-
Step 500
500 (this color)
#337CE7
oklch(59.8% 0.178 258.4)
-
Step 600
600
#186DE1
oklch(55.6% 0.193 258.4)
-
Step 700
700
#075AC4
oklch(49.1% 0.18 258.5)
-
Step 800
800
#0D4A9E
oklch(42.6% 0.149 258.5)
-
Step 900
900
#143F7E
oklch(37.7% 0.117 258.5)
-
Step 950
950
#0D264A
oklch(27.1% 0.074 257.9)
#337CE7 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) | #4187EB | 0.033 |
| Deuteranopia (no green cones) | #0B76E5 | 0.026 |
| Tritanopia (no blue cones) | #0096A6 | 0.138 |
| Achromatopsia (no color) | #7E7E7E | 0.178 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #337CE7
#337CE7
oklch(59.8% 0.178 258.4)
- #A77500
#A77500
oklch(59.8% 0.124 78.8)
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 #337CE7, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Clear Blue #247AFD ΔE 0.035
- Cerulean Blue #056EEE ΔE 0.046
- Royal Blue #4169E1 ΔE 0.047
- Dark Sky Blue #448EE4 ΔE 0.053
- Water Blue #0E87CC ΔE 0.057
- Dodger Blue #1E90FF ΔE 0.058
- Soft Blue #6488EA ΔE 0.060
- Cornflower #6A79F7 ΔE 0.060
Use #337CE7 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.