#397FBD
Closest named color: Windows Blue (#3778BF). oklch(58.1% 0.119 248.2), rgb(57, 127, 189).
Aa
Black text reads best on this color (4.94:1).
About this color
#397FBD is a medium-dark, moderately saturated blue. In OKLCH its lightness is 58%, its chroma 0.119 and its hue 248°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.021 away. Black text reads best on it, at 4.94:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | moderately saturated (0.119) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.94:1 |
| White text | 4.24:1 |
Values
| HEX | #397FBD |
| RGB | rgb(57, 127, 189) |
| HSL | hsl(208, 54%, 48%) |
| OKLCH | oklch(58.1% 0.119 248.2) |
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 #397FBD | 4.24:1 | AA large text | Lc -74.6 | Content text, not long reading |
| Black text on #397FBD | 4.94:1 | AA | Lc 35.0 | Non-text elements, placeholder text |
| #397FBD text on white | 4.24:1 | AA large text | Lc 69.1 | Content text, not long reading |
| #397FBD text on black | 4.94:1 | AA | Lc -32.6 | 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
#E2EBF4
oklch(93.6% 0.016 248)
-
Step 200
200
#CADBEC
oklch(88.4% 0.03 248.2)
-
Step 300
300
#A6C4E2
oklch(80.8% 0.054 248.5)
-
Step 400
400
#75A5D4
oklch(70.6% 0.086 248.6)
-
Step 500
500
#508EC8
oklch(63% 0.109 248.5)
-
Step 600
600 (this color)
#397FBD
oklch(58.1% 0.119 248.2)
-
Step 700
700
#23649C
oklch(49% 0.111 248.4)
-
Step 800
800
#1F527E
oklch(42.7% 0.091 248)
-
Step 900
900
#1F4465
oklch(37.6% 0.071 247.8)
-
Step 950
950
#13283B
oklch(26.9% 0.045 247.5)
#397FBD 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) | #6382C0 | 0.045 |
| Deuteranopia (no green cones) | #5175BC | 0.033 |
| Tritanopia (no blue cones) | #008E95 | 0.090 |
| Achromatopsia (no color) | #7B7B7B | 0.119 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #397FBD
#397FBD
oklch(58.1% 0.119 248.2)
- #A86B18
#A86B18
oklch(58.1% 0.119 68)
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 #397FBD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.021
- Steel Blue #4682B4 ΔE 0.021
- Cool Blue #4984B8 ΔE 0.023
- Water Blue #0E87CC ΔE 0.031
- Nice Blue #107AB0 ΔE 0.035
- Off Blue #5684AE ΔE 0.041
- Flat Blue #3C73A8 ΔE 0.042
- Blue NCS #118AB2 ΔE 0.043
Use #397FBD 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.