#3F91CF
Closest named color: Dark Sky Blue (#448EE4). oklch(63.4% 0.123 244.5), rgb(63, 145, 207).
Aa
Black text reads best on this color (6.16:1).
About this color
#3F91CF is a medium-light, moderately saturated blue. In OKLCH its lightness is 63%, its chroma 0.123 and its hue 244°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.035 away. Black text reads best on it, at 6.16:1.
| Hue family | Blues |
| Lightness | medium-light (63%) |
| Chroma | moderately saturated (0.123) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 6.16:1 |
| White text | 3.40:1 |
Values
| HEX | #3F91CF |
| RGB | rgb(63, 145, 207) |
| HSL | hsl(206, 60%, 53%) |
| OKLCH | oklch(63.4% 0.123 244.5) |
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 #3F91CF | 3.40:1 | AA large text | Lc -66.7 | Content text, not long reading |
| Black text on #3F91CF | 6.16:1 | AA | Lc 42.8 | Non-text elements, placeholder text |
| #3F91CF text on white | 3.40:1 | AA large text | Lc 61.3 | Content text, not long reading |
| #3F91CF text on black | 6.16:1 | AA | Lc -40.4 | 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
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#E1EBF5
oklch(93.5% 0.017 248)
-
Step 200
200
#C7DCEE
oklch(88.4% 0.034 244)
-
Step 300
300
#A1C6E5
oklch(81% 0.059 243.9)
-
Step 400
400
#6BA7D8
oklch(70.7% 0.095 244.4)
-
Step 500
500 (this color)
#3F91CF
oklch(63.4% 0.123 244.5)
-
Step 600
600
#1179BB
oklch(55.6% 0.133 244.5)
-
Step 700
700
#0066A0
oklch(49.2% 0.121 244)
-
Step 800
800
#085383
oklch(42.7% 0.103 244.8)
-
Step 900
900
#144569
oklch(37.7% 0.08 244.8)
-
Step 950
950
#0E293D
oklch(27.1% 0.05 243.6)
#3F91CF 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) | #7593D2 | 0.055 |
| Deuteranopia (no green cones) | #6185CE | 0.042 |
| Tritanopia (no blue cones) | #00A0A7 | 0.088 |
| Achromatopsia (no color) | #8B8B8B | 0.123 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F91CF
#3F91CF
oklch(63.4% 0.123 244.5)
- #BD792D
#BD792D
oklch(63.5% 0.123 64.7)
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 #3F91CF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.035
- Water Blue #0E87CC ΔE 0.040
- Faded Blue #658CBB ΔE 0.042
- Cool Blue #4984B8 ΔE 0.044
- Chefchaouen Blue #4895EF ΔE 0.049
- Steel Blue #4682B4 ΔE 0.052
- Blue NCS #118AB2 ΔE 0.055
- Dusty Blue #5A86AD ΔE 0.055
Use #3F91CF 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.