#427FBB
Closest named color: Steel Blue (#4682B4). oklch(58.3% 0.112 250), rgb(66, 127, 187).
Aa
Black text reads best on this color (4.98:1).
About this color
#427FBB is a medium-dark, moderately saturated blue. In OKLCH its lightness is 58%, its chroma 0.112 and its hue 250°. Its hue sits on the cool side of the wheel. The nearest named color is Steel Blue (#4682B4), ΔE 0.016 away. Black text reads best on it, at 4.98:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | moderately saturated (0.112) |
| Temperature | cool |
| Nearest name | Steel Blue (#4682B4) |
| Black text | 4.98:1 |
| White text | 4.21:1 |
Values
| HEX | #427FBB |
| RGB | rgb(66, 127, 187) |
| HSL | hsl(210, 48%, 50%) |
| OKLCH | oklch(58.3% 0.112 250) |
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 #427FBB | 4.21:1 | AA large text | Lc -74.3 | Content text, not long reading |
| Black text on #427FBB | 4.98:1 | AA | Lc 35.2 | Non-text elements, placeholder text |
| #427FBB text on white | 4.21:1 | AA large text | Lc 68.8 | Content text, not long reading |
| #427FBB text on black | 4.98:1 | AA | Lc -32.8 | 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
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E3EBF4
oklch(93.7% 0.015 251.2)
-
Step 200
200
#CCDBEB
oklch(88.5% 0.027 249.9)
-
Step 300
300
#A9C4E1
oklch(81% 0.051 250.3)
-
Step 400
400
#7AA5D2
oklch(70.8% 0.081 250.1)
-
Step 500
500
#568EC6
oklch(63.2% 0.104 249.8)
-
Step 600
600 (this color)
#427FBB
oklch(58.3% 0.112 250)
-
Step 700
700
#2C6499
oklch(49.2% 0.104 249.7)
-
Step 800
800
#25527C
oklch(42.8% 0.086 249.1)
-
Step 900
900
#234464
oklch(37.7% 0.068 249.4)
-
Step 950
950
#15283B
oklch(27.1% 0.044 249.7)
#427FBB 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) | #6582BE | 0.040 |
| Deuteranopia (no green cones) | #5476BA | 0.028 |
| Tritanopia (no blue cones) | #008D94 | 0.089 |
| Achromatopsia (no color) | #7B7B7B | 0.112 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #427FBB
#427FBB
oklch(58.3% 0.112 250)
- #A56E22
#A56E22
oklch(58.3% 0.112 70.2)
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 #427FBB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Steel Blue #4682B4 ΔE 0.016
- Cool Blue #4984B8 ΔE 0.018
- Windows Blue #3778BF ΔE 0.025
- Off Blue #5684AE ΔE 0.034
- Water Blue #0E87CC ΔE 0.036
- Nice Blue #107AB0 ΔE 0.039
- Dusty Blue #5A86AD ΔE 0.042
- Flat Blue #3C73A8 ΔE 0.042
Use #427FBB 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.