#123F9C
Closest named color: Sapphire (#2138AB). oklch(40.1% 0.159 262.4), rgb(18, 63, 156).
Aa
White text reads best on this color (9.47:1).
About this color
#123F9C is a dark, vivid blue. In OKLCH its lightness is 40%, its chroma 0.159 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Sapphire (#2138AB), ΔE 0.030 away. White text reads best on it, at 9.47:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | vivid (0.159) |
| Temperature | cool |
| Nearest name | Sapphire (#2138AB) |
| Black text | 2.21:1 |
| White text | 9.47:1 |
Values
| HEX | #123F9C |
| RGB | rgb(18, 63, 156) |
| HSL | hsl(220, 79%, 34%) |
| OKLCH | oklch(40.1% 0.159 262.4) |
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 #123F9C | 9.47:1 | AAA | Lc -95.6 | Preferred for body text |
| Black text on #123F9C | 2.21:1 | Fails | Lc 12.7 | Not readable |
| #123F9C text on white | 9.47:1 | AAA | Lc 91.2 | Preferred for body text |
| #123F9C text on black | 2.21:1 | Fails | Lc -11.1 | Not readable |
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 900.
-
Step 50
50
#F1F6FF
oklch(97.2% 0.013 262.4)
-
Step 100
100
#DFEAFF
oklch(93.5% 0.031 263.5)
-
Step 200
200
#C6DAFF
oklch(88.5% 0.056 262.8)
-
Step 300
300
#9FC1FF
oklch(80.9% 0.096 262.2)
-
Step 400
400
#6B9EFF
oklch(70.7% 0.153 262.2)
-
Step 500
500
#4381FF
oklch(63% 0.199 262.5)
-
Step 600
600
#1361FF
oklch(55.6% 0.245 262.4)
-
Step 700
700
#004DE2
oklch(49.1% 0.234 262.4)
-
Step 800
800
#003EBB
oklch(42.6% 0.203 262.4)
-
Step 900
900 (this color)
#123F9C
oklch(40.1% 0.159 262.4)
-
Step 950
950
#082257
oklch(27.1% 0.101 262.2)
#123F9C 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) | #004C9F | 0.033 |
| Deuteranopia (no green cones) | #00409A | 0.009 |
| Tritanopia (no blue cones) | #005767 | 0.122 |
| Achromatopsia (no color) | #464646 | 0.160 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #123F9C
#123F9C
oklch(40.1% 0.159 262.4)
- #5E4300
#5E4300
oklch(40.2% 0.083 82.4)
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 #123F9C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sapphire #2138AB ΔE 0.030
- Cobalt #1E488F ΔE 0.035
- Twilight Blue #0A437A ΔE 0.059
- Blueberry #464196 ΔE 0.061
- Light Navy #155084 ΔE 0.065
- Dusk Blue #26538D ΔE 0.067
- Dark Slate Blue #483D8B ΔE 0.069
- Blue Blue #2242C7 ΔE 0.072
Use #123F9C 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.