#397FAC
Closest named color: Steel Blue (#4682B4). oklch(57.2% 0.099 239.9), rgb(57, 127, 172).
Aa
Black text reads best on this color (4.80:1).
About this color
#397FAC is a medium-dark, moderately saturated blue. In OKLCH its lightness is 57%, its chroma 0.099 and its hue 240°. Its hue sits on the cool side of the wheel. The nearest named color is Steel Blue (#4682B4), ΔE 0.019 away. Black text reads best on it, at 4.80:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | moderately saturated (0.099) |
| Temperature | cool |
| Nearest name | Steel Blue (#4682B4) |
| Black text | 4.80:1 |
| White text | 4.37:1 |
Values
| HEX | #397FAC |
| RGB | rgb(57, 127, 172) |
| HSL | hsl(203, 50%, 45%) |
| OKLCH | oklch(57.2% 0.099 239.9) |
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 #397FAC | 4.37:1 | AA large text | Lc -75.5 | Fine for body text |
| Black text on #397FAC | 4.80:1 | AA | Lc 34.0 | Non-text elements, placeholder text |
| #397FAC text on white | 4.37:1 | AA large text | Lc 70.0 | Content text, not long reading |
| #397FAC text on black | 4.80:1 | AA | Lc -31.6 | 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
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E3EBF2
oklch(93.6% 0.013 244.3)
-
Step 200
200
#CBDCE8
oklch(88.5% 0.025 238.4)
-
Step 300
300
#A7C5DB
oklch(80.8% 0.045 239.9)
-
Step 400
400
#77A7C9
oklch(70.7% 0.072 239.9)
-
Step 500
500
#5291BB
oklch(63.2% 0.091 239.6)
-
Step 600
600 (this color)
#397FAC
oklch(57.2% 0.099 239.9)
-
Step 700
700
#26678F
oklch(49.1% 0.091 239.7)
-
Step 800
800
#215474
oklch(42.7% 0.076 239.6)
-
Step 900
900
#21465E
oklch(37.8% 0.059 239.4)
-
Step 950
950
#142937
oklch(27% 0.038 239.4)
#397FAC 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) | #6A7FAE | 0.052 |
| Deuteranopia (no green cones) | #5B74AB | 0.043 |
| Tritanopia (no blue cones) | #008A8E | 0.070 |
| Achromatopsia (no color) | #797979 | 0.099 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #397FAC
#397FAC
oklch(57.2% 0.099 239.9)
- #A26937
#A26937
oklch(57.2% 0.098 60.1)
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 #397FAC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Steel Blue #4682B4 ΔE 0.019
- Cerulean #457B9D ΔE 0.024
- Cool Blue #4984B8 ΔE 0.027
- Nice Blue #107AB0 ΔE 0.029
- Stormy Blue #507B9C ΔE 0.030
- Blue NCS #118AB2 ΔE 0.033
- Off Blue #5684AE ΔE 0.033
- Dull Blue #49759C ΔE 0.033
Use #397FAC 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.