#183F4B
Closest named color: Dark Blue Grey (#1F3B4D). oklch(34.5% 0.048 221.1), rgb(24, 63, 75).
Aa
White text reads best on this color (11.34:1).
About this color
#183F4B is a dark, muted teal or cyan. In OKLCH its lightness is 35%, its chroma 0.048 and its hue 221°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Blue Grey (#1F3B4D), ΔE 0.016 away. White text reads best on it, at 11.34:1.
| Hue family | Teals and cyans |
| Lightness | dark (35%) |
| Chroma | muted (0.048) |
| Temperature | cool |
| Nearest name | Dark Blue Grey (#1F3B4D) |
| Black text | 1.85:1 |
| White text | 11.34:1 |
Values
| HEX | #183F4B |
| RGB | rgb(24, 63, 75) |
| HSL | hsl(194, 52%, 19%) |
| OKLCH | oklch(34.5% 0.048 221.1) |
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 #183F4B | 11.34:1 | AAA | Lc -99.8 | Preferred for body text |
| Black text on #183F4B | 1.85:1 | Fails | Lc 7.9 | Not readable |
| #183F4B text on white | 11.34:1 | AAA | Lc 96.0 | Preferred for body text |
| #183F4B text on black | 1.85:1 | Fails | Lc 0.0 | 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
#F2F6F8
oklch(97.1% 0.005 228.8)
-
Step 100
100
#E3ECEF
oklch(93.7% 0.01 219.6)
-
Step 200
200
#CBDCE3
oklch(88.4% 0.021 224.3)
-
Step 300
300
#A8C6D1
oklch(80.8% 0.036 222)
-
Step 400
400
#78A9BA
oklch(70.6% 0.058 221.5)
-
Step 500
500
#5294A9
oklch(63.1% 0.074 220.7)
-
Step 600
600
#347E95
oklch(55.6% 0.08 221.6)
-
Step 700
700
#256A7F
oklch(49.1% 0.075 221.8)
-
Step 800
800
#215767
oklch(42.8% 0.062 220.6)
-
Step 900
900 (this color)
#183F4B
oklch(34.5% 0.048 221.1)
-
Step 950
950
#142A31
oklch(27% 0.031 220.6)
#183F4B 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) | #383D4C | 0.040 |
| Deuteranopia (no green cones) | #30384B | 0.035 |
| Tritanopia (no blue cones) | #004343 | 0.027 |
| Achromatopsia (no color) | #3A3A3A | 0.048 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #183F4B
#183F4B
oklch(34.5% 0.048 221.1)
- #4F3125
#4F3125
oklch(34.6% 0.048 42.5)
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 #183F4B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Blue Grey #1F3B4D ΔE 0.016
- Midnight Green #073B4C ΔE 0.020
- Charcoal #264653 ΔE 0.031
- Onyx #343A40 ΔE 0.037
- Dark Grey Blue #29465B ΔE 0.040
- Gunmetal #293241 ΔE 0.044
- Prussian Blue #1D3557 ΔE 0.044
- Dark Teal #014D4E ΔE 0.046
Use #183F4B 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.