#3970BD
Closest named color: Windows Blue (#3778BF). oklch(54.6% 0.134 257.3), rgb(57, 112, 189).
Aa
White text reads best on this color (4.96:1).
About this color
#3970BD is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.134 and its hue 257°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.022 away. White text reads best on it, at 4.96:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.134) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.22:1 |
| White text | 4.96:1 |
Values
| HEX | #3970BD |
| RGB | rgb(57, 112, 189) |
| HSL | hsl(215, 54%, 48%) |
| OKLCH | oklch(54.6% 0.134 257.3) |
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 #3970BD | 4.96:1 | AA | Lc -79.5 | Fine for body text |
| Black text on #3970BD | 4.22:1 | AA large text | Lc 30.0 | Dividers and decoration only |
| #3970BD text on white | 4.96:1 | AA | Lc 74.1 | Content text, not long reading |
| #3970BD text on black | 4.22:1 | AA large text | Lc -27.6 | Dividers and decoration only |
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
#E3EBF6
oklch(93.7% 0.017 256.3)
-
Step 200
200
#CCDAF0
oklch(88.5% 0.034 259.4)
-
Step 300
300
#A8C3E8
oklch(81% 0.06 256.3)
-
Step 400
400
#7AA2DC
oklch(70.6% 0.096 257.6)
-
Step 500
500
#578AD3
oklch(63% 0.124 257.4)
-
Step 600
600 (this color)
#3970BD
oklch(54.6% 0.134 257.3)
-
Step 700
700
#2E60A6
oklch(49.1% 0.125 257.3)
-
Step 800
800
#274F86
oklch(42.8% 0.102 256.9)
-
Step 900
900
#24426C
oklch(37.8% 0.081 257.1)
-
Step 950
950
#16273F
oklch(27.1% 0.05 257.1)
#3970BD 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) | #4C76C0 | 0.027 |
| Deuteranopia (no green cones) | #376ABB | 0.017 |
| Tritanopia (no blue cones) | #00828D | 0.107 |
| Achromatopsia (no color) | #707070 | 0.134 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3970BD
#3970BD
oklch(54.6% 0.134 257.3)
- #956600
#956600
oklch(54.6% 0.114 77.1)
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 #3970BD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.022
- French Blue #436BAD ΔE 0.027
- Mid Blue #276AB3 ΔE 0.028
- Flat Blue #3C73A8 ΔE 0.036
- Nice Blue #107AB0 ΔE 0.043
- Muted Blue #3B719F ΔE 0.048
- Dull Blue #49759C ΔE 0.059
- Steel Blue #4682B4 ΔE 0.059
Use #3970BD 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.