#3F809B
Closest named color: Cerulean (#457B9D). oklch(56.8% 0.078 227.7), rgb(63, 128, 155).
Aa
Black text reads best on this color (4.77:1).
About this color
#3F809B is a medium-dark, moderately saturated teal or cyan. In OKLCH its lightness is 57%, its chroma 0.078 and its hue 228°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean (#457B9D), ΔE 0.016 away. Black text reads best on it, at 4.77:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (57%) |
| Chroma | moderately saturated (0.078) |
| Temperature | cool |
| Nearest name | Cerulean (#457B9D) |
| Black text | 4.77:1 |
| White text | 4.40:1 |
Values
| HEX | #3F809B |
| RGB | rgb(63, 128, 155) |
| HSL | hsl(198, 42%, 43%) |
| OKLCH | oklch(56.8% 0.078 227.7) |
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 #3F809B | 4.40:1 | AA large text | Lc -75.8 | Fine for body text |
| Black text on #3F809B | 4.77:1 | AA | Lc 33.8 | Non-text elements, placeholder text |
| #3F809B text on white | 4.40:1 | AA large text | Lc 70.3 | Content text, not long reading |
| #3F809B text on black | 4.77:1 | AA | Lc -31.3 | 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
#F2F6F8
oklch(97.1% 0.005 228.8)
-
Step 100
100
#E3EBEF
oklch(93.5% 0.01 228.9)
-
Step 200
200
#CCDCE3
oklch(88.5% 0.02 225.7)
-
Step 300
300
#AAC6D3
oklch(81% 0.035 227.5)
-
Step 400
400
#7BA8BC
oklch(70.6% 0.056 227.2)
-
Step 500
500
#5892AC
oklch(63% 0.072 228.5)
-
Step 600
600 (this color)
#3F809B
oklch(56.8% 0.078 227.7)
-
Step 700
700
#2D6981
oklch(49.2% 0.072 227.4)
-
Step 800
800
#265569
oklch(42.6% 0.061 228.5)
-
Step 900
900
#244755
oklch(37.8% 0.047 226.2)
-
Step 950
950
#162932
oklch(26.9% 0.03 229.7)
#3F809B 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) | #727E9C | 0.058 |
| Deuteranopia (no green cones) | #65749B | 0.051 |
| Tritanopia (no blue cones) | #008889 | 0.051 |
| Achromatopsia (no color) | #787878 | 0.078 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F809B
#3F809B
oklch(56.8% 0.078 227.7)
- #9D694E
#9D694E
oklch(56.9% 0.078 48.1)
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 #3F809B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean #457B9D ΔE 0.016
- Stormy Blue #507B9C ΔE 0.021
- Teal Blue #01889F ΔE 0.032
- Dull Blue #49759C ΔE 0.033
- Metallic Blue #4F738E ΔE 0.039
- Ocean #017B92 ΔE 0.039
- Off Blue #5684AE ΔE 0.040
- Steel Blue #4682B4 ΔE 0.040
Use #3F809B 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.