#123F5F
Closest named color: Dark Blue Grey (#1F3B4D). oklch(35.4% 0.074 243.9), rgb(18, 63, 95).
Aa
White text reads best on this color (11.04:1).
About this color
#123F5F is a dark, moderately saturated blue. In OKLCH its lightness is 35%, its chroma 0.074 and its hue 244°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Blue Grey (#1F3B4D), ΔE 0.032 away. White text reads best on it, at 11.04:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | moderately saturated (0.074) |
| Temperature | cool |
| Nearest name | Dark Blue Grey (#1F3B4D) |
| Black text | 1.90:1 |
| White text | 11.04:1 |
Values
| HEX | #123F5F |
| RGB | rgb(18, 63, 95) |
| HSL | hsl(205, 68%, 22%) |
| OKLCH | oklch(35.4% 0.074 243.9) |
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 #123F5F | 11.04:1 | AAA | Lc -99.1 | Preferred for body text |
| Black text on #123F5F | 1.90:1 | Fails | Lc 8.6 | Not readable |
| #123F5F text on white | 11.04:1 | AAA | Lc 95.3 | Preferred for body text |
| #123F5F text on black | 1.90:1 | Fails | Lc -7.4 | 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
#F1F6FA
oklch(97.1% 0.008 241.7)
-
Step 100
100
#E1EBF4
oklch(93.5% 0.016 245.1)
-
Step 200
200
#C9DCEC
oklch(88.5% 0.03 243.4)
-
Step 300
300
#A3C5E2
oklch(80.8% 0.055 244.3)
-
Step 400
400
#6FA7D4
oklch(70.7% 0.089 243.7)
-
Step 500
500
#4690C8
oklch(63.1% 0.112 243.9)
-
Step 600
600
#2179B5
oklch(55.5% 0.123 244)
-
Step 700
700
#11669C
oklch(49.1% 0.114 243.8)
-
Step 800
800
#14537E
oklch(42.6% 0.094 244)
-
Step 900
900 (this color)
#123F5F
oklch(35.4% 0.074 243.9)
-
Step 950
950
#10293B
oklch(27.1% 0.046 242.4)
#123F5F 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) | #304060 | 0.032 |
| Deuteranopia (no green cones) | #25395E | 0.024 |
| Tritanopia (no blue cones) | #00474A | 0.053 |
| Achromatopsia (no color) | #3C3C3C | 0.074 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #123F5F
#123F5F
oklch(35.4% 0.074 243.9)
- #563209
#563209
oklch(35.5% 0.074 63.6)
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 #123F5F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Blue Grey #1F3B4D ΔE 0.032
- Prussian Blue #1D3557 ΔE 0.032
- Marine Blue #01386A ΔE 0.034
- Dark Grey Blue #29465B ΔE 0.035
- Midnight Green #073B4C ΔE 0.036
- Charcoal #264653 ΔE 0.040
- Twilight Blue #0A437A ΔE 0.046
- Marine #042E60 ΔE 0.057
Use #123F5F 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.