#397CB0
Closest named color: Steel Blue (#4682B4). oklch(56.7% 0.105 244.7), rgb(57, 124, 176).
Aa
Black text reads best on this color (4.68:1).
About this color
#397CB0 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 57%, its chroma 0.105 and its hue 245°. Its hue sits on the cool side of the wheel. The nearest named color is Steel Blue (#4682B4), ΔE 0.022 away. Black text reads best on it, at 4.68:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | moderately saturated (0.105) |
| Temperature | cool |
| Nearest name | Steel Blue (#4682B4) |
| Black text | 4.68:1 |
| White text | 4.48:1 |
Values
| HEX | #397CB0 |
| RGB | rgb(57, 124, 176) |
| HSL | hsl(206, 51%, 46%) |
| OKLCH | oklch(56.7% 0.105 244.7) |
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 #397CB0 | 4.48:1 | AA large text | Lc -76.3 | Fine for body text |
| Black text on #397CB0 | 4.68:1 | AA | Lc 33.2 | Non-text elements, placeholder text |
| #397CB0 text on white | 4.48:1 | AA large text | Lc 70.9 | Content text, not long reading |
| #397CB0 text on black | 4.68:1 | AA | Lc -30.8 | 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
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E3EBF3
oklch(93.6% 0.014 248)
-
Step 200
200
#CBDBEA
oklch(88.4% 0.027 246.4)
-
Step 300
300
#A8C5DE
oklch(81% 0.047 244.4)
-
Step 400
400
#78A6CD
oklch(70.7% 0.076 244.7)
-
Step 500
500
#538FC0
oklch(63% 0.097 244.9)
-
Step 600
600 (this color)
#397CB0
oklch(56.7% 0.105 244.7)
-
Step 700
700
#286594
oklch(49% 0.098 245.2)
-
Step 800
800
#225378
oklch(42.7% 0.081 244.3)
-
Step 900
900
#224561
oklch(37.8% 0.063 244.7)
-
Step 950
950
#142839
oklch(26.9% 0.041 245.8)
#397CB0 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) | #657DB2 | 0.047 |
| Deuteranopia (no green cones) | #5472AF | 0.036 |
| Tritanopia (no blue cones) | #00898E | 0.079 |
| Achromatopsia (no color) | #777777 | 0.106 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #397CB0
#397CB0
oklch(56.7% 0.105 244.7)
- #A1682A
#A1682A
oklch(56.7% 0.106 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 #397CB0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Steel Blue #4682B4 ΔE 0.022
- Nice Blue #107AB0 ΔE 0.024
- Flat Blue #3C73A8 ΔE 0.026
- Windows Blue #3778BF ΔE 0.029
- Cool Blue #4984B8 ΔE 0.030
- Cerulean #457B9D ΔE 0.030
- Dull Blue #49759C ΔE 0.034
- Stormy Blue #507B9C ΔE 0.036
Use #397CB0 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.