#437ACE
Closest named color: Windows Blue (#3778BF). oklch(58.3% 0.142 258.7), rgb(67, 122, 206).
Aa
Black text reads best on this color (4.91:1).
About this color
#437ACE is a medium-dark, vivid blue. In OKLCH its lightness is 58%, its chroma 0.142 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.026 away. Black text reads best on it, at 4.91:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | vivid (0.142) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.91:1 |
| White text | 4.27:1 |
Values
| HEX | #437ACE |
| RGB | rgb(67, 122, 206) |
| HSL | hsl(216, 59%, 54%) |
| OKLCH | oklch(58.3% 0.142 258.7) |
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 #437ACE | 4.27:1 | AA large text | Lc -74.8 | Content text, not long reading |
| Black text on #437ACE | 4.91:1 | AA | Lc 34.8 | Non-text elements, placeholder text |
| #437ACE text on white | 4.27:1 | AA large text | Lc 69.3 | Content text, not long reading |
| #437ACE text on black | 4.91:1 | AA | Lc -32.4 | 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 600.
-
Step 50
50
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E3EAF7
oklch(93.6% 0.019 263)
-
Step 200
200
#CBDAF1
oklch(88.4% 0.036 258.9)
-
Step 300
300
#A8C2EA
oklch(80.8% 0.064 258.9)
-
Step 400
400
#79A2E0
oklch(70.7% 0.102 258.5)
-
Step 500
500
#5689D8
oklch(63% 0.132 258.9)
-
Step 600
600 (this color)
#437ACE
oklch(58.3% 0.142 258.7)
-
Step 700
700
#2D5FAA
oklch(49.1% 0.132 258.5)
-
Step 800
800
#264E8A
oklch(42.7% 0.11 258.4)
-
Step 900
900
#24416E
oklch(37.7% 0.085 258.9)
-
Step 950
950
#152641
oklch(26.9% 0.056 259.3)
#437ACE 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) | #5381D1 | 0.027 |
| Deuteranopia (no green cones) | #3D74CC | 0.018 |
| Tritanopia (no blue cones) | #008D9A | 0.114 |
| Achromatopsia (no color) | #7A7A7A | 0.142 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #437ACE
#437ACE
oklch(58.3% 0.142 258.7)
- #A27100
#A27100
oklch(58.4% 0.122 78.5)
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 #437ACE, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.026
- Water Blue #0E87CC ΔE 0.042
- Cool Blue #4984B8 ΔE 0.049
- Steel Blue #4682B4 ΔE 0.051
- Royal Blue #4169E1 ΔE 0.056
- Nice Blue #107AB0 ΔE 0.059
- Dark Sky Blue #448EE4 ΔE 0.059
- French Blue #436BAD ΔE 0.060
Use #437ACE 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.