#397BA3
Closest named color: Cerulean (#457B9D). oklch(55.8% 0.091 238.1), rgb(57, 123, 163).
Aa
White text reads best on this color (4.62:1).
About this color
#397BA3 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 56%, its chroma 0.091 and its hue 238°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean (#457B9D), ΔE 0.013 away. White text reads best on it, at 4.62:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.091) |
| Temperature | cool |
| Nearest name | Cerulean (#457B9D) |
| Black text | 4.53:1 |
| White text | 4.62:1 |
Values
| HEX | #397BA3 |
| RGB | rgb(57, 123, 163) |
| HSL | hsl(203, 48%, 43%) |
| OKLCH | oklch(55.8% 0.091 238.1) |
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 #397BA3 | 4.62:1 | AA | Lc -77.4 | Fine for body text |
| Black text on #397BA3 | 4.53:1 | AA | Lc 32.1 | Non-text elements, placeholder text |
| #397BA3 text on white | 4.62:1 | AA | Lc 71.9 | Content text, not long reading |
| #397BA3 text on black | 4.53:1 | AA | Lc -29.7 | 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
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E3EBF1
oklch(93.6% 0.012 239.9)
-
Step 200
200
#CCDCE7
oklch(88.6% 0.023 237.7)
-
Step 300
300
#A9C5D9
oklch(80.9% 0.041 239.1)
-
Step 400
400
#7AA7C5
oklch(70.7% 0.065 238.1)
-
Step 500
500
#5691B7
oklch(63.2% 0.084 238.3)
-
Step 600
600 (this color)
#397BA3
oklch(55.8% 0.091 238.1)
-
Step 700
700
#2A678B
oklch(49.1% 0.085 238)
-
Step 800
800
#255471
oklch(42.7% 0.07 238.6)
-
Step 900
900
#23465B
oklch(37.8% 0.054 236.9)
-
Step 950
950
#152935
oklch(27% 0.034 236.3)
#397BA3 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) | #687BA5 | 0.051 |
| Deuteranopia (no green cones) | #5A70A2 | 0.043 |
| Tritanopia (no blue cones) | #008589 | 0.063 |
| Achromatopsia (no color) | #757575 | 0.092 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #397BA3
#397BA3
oklch(55.8% 0.091 238.1)
- #9C653A
#9C653A
oklch(55.7% 0.092 57.4)
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 #397BA3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean #457B9D ΔE 0.013
- Dull Blue #49759C ΔE 0.021
- Stormy Blue #507B9C ΔE 0.023
- Flat Blue #3C73A8 ΔE 0.027
- Muted Blue #3B719F ΔE 0.029
- Nice Blue #107AB0 ΔE 0.029
- Steel Blue #4682B4 ΔE 0.034
- Metallic Blue #4F738E ΔE 0.037
Use #397BA3 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.