#183EA1
Closest named color: Sapphire (#2138AB). oklch(40.6% 0.166 264.2), rgb(24, 62, 161).
Aa
White text reads best on this color (9.36:1).
About this color
#183EA1 is a dark, vivid blue. In OKLCH its lightness is 41%, its chroma 0.166 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Sapphire (#2138AB), ΔE 0.021 away. White text reads best on it, at 9.36:1.
| Hue family | Blues |
| Lightness | dark (41%) |
| Chroma | vivid (0.166) |
| Temperature | cool |
| Nearest name | Sapphire (#2138AB) |
| Black text | 2.24:1 |
| White text | 9.36:1 |
Values
| HEX | #183EA1 |
| RGB | rgb(24, 62, 161) |
| HSL | hsl(223, 74%, 36%) |
| OKLCH | oklch(40.6% 0.166 264.2) |
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 #183EA1 | 9.36:1 | AAA | Lc -95.3 | Preferred for body text |
| Black text on #183EA1 | 2.24:1 | Fails | Lc 13.0 | Not readable |
| #183EA1 text on white | 9.36:1 | AAA | Lc 90.9 | Preferred for body text |
| #183EA1 text on black | 2.24:1 | Fails | Lc -11.4 | 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 800.
-
Step 50
50
#F1F6FF
oklch(97.2% 0.013 262.4)
-
Step 100
100
#E0EAFD
oklch(93.5% 0.028 263.4)
-
Step 200
200
#C7DAFE
oklch(88.6% 0.054 263.2)
-
Step 300
300
#A2C0FF
oklch(80.9% 0.096 264.7)
-
Step 400
400
#709DFF
oklch(70.7% 0.152 264.2)
-
Step 500
500
#4A80FF
oklch(63.1% 0.198 264.2)
-
Step 600
600
#2F65EF
oklch(55.6% 0.216 264.2)
-
Step 700
700
#2253D0
oklch(49.2% 0.2 264)
-
Step 800
800 (this color)
#183EA1
oklch(40.6% 0.166 264.2)
-
Step 900
900
#1D3B85
oklch(37.7% 0.13 264.4)
-
Step 950
950
#11234E
oklch(26.9% 0.083 264.4)
#183EA1 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) | #004DA4 | 0.037 |
| Deuteranopia (no green cones) | #00409F | 0.012 |
| Tritanopia (no blue cones) | #005869 | 0.129 |
| Achromatopsia (no color) | #474747 | 0.166 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #183EA1
#183EA1
oklch(40.6% 0.166 264.2)
- #5E4400
#5E4400
oklch(40.4% 0.083 83.7)
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 #183EA1, closest first.
No curated palette has a color within ΔE 0.04 of #183EA1.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sapphire #2138AB ΔE 0.021
- Cobalt #1E488F ΔE 0.041
- Blueberry #464196 ΔE 0.060
- Blue Blue #2242C7 ΔE 0.064
- Twilight Blue #0A437A ΔE 0.068
- Dark Slate Blue #483D8B ΔE 0.069
- Dusk Blue #26538D ΔE 0.071
- Light Navy #155084 ΔE 0.072
Use #183EA1 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.