#1B457F
Closest named color: Twilight Blue (#0A437A). oklch(39.4% 0.109 257.3), rgb(27, 69, 127).
Aa
White text reads best on this color (9.52:1).
About this color
#1B457F is a dark, moderately saturated blue. In OKLCH its lightness is 39%, its chroma 0.109 and its hue 257°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.016 away. White text reads best on it, at 9.52:1.
| Hue family | Blues |
| Lightness | dark (39%) |
| Chroma | moderately saturated (0.109) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.20:1 |
| White text | 9.52:1 |
Values
| HEX | #1B457F |
| RGB | rgb(27, 69, 127) |
| HSL | hsl(215, 65%, 30%) |
| OKLCH | oklch(39.4% 0.109 257.3) |
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 #1B457F | 9.52:1 | AAA | Lc -96.0 | Preferred for body text |
| Black text on #1B457F | 2.20:1 | Fails | Lc 12.3 | Not readable |
| #1B457F text on white | 9.52:1 | AAA | Lc 91.7 | Preferred for body text |
| #1B457F text on black | 2.20:1 | Fails | Lc -10.7 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E0EBFA
oklch(93.6% 0.024 256.1)
-
Step 200
200
#C7DBF8
oklch(88.6% 0.046 257.6)
-
Step 300
300
#A0C3F5
oklch(80.9% 0.081 257.3)
-
Step 400
400
#6BA2F1
oklch(70.8% 0.13 257.5)
-
Step 500
500
#4088EC
oklch(63.1% 0.167 257.3)
-
Step 600
600
#1C6FDA
oklch(55.5% 0.181 257.3)
-
Step 700
700
#0D5CBD
oklch(49% 0.168 257.4)
-
Step 800
800
#104C99
oklch(42.7% 0.139 257.3)
-
Step 900
900 (this color)
#1B457F
oklch(39.4% 0.109 257.3)
-
Step 950
950
#0E2647
oklch(27% 0.068 257.1)
#1B457F 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) | #284A81 | 0.021 |
| Deuteranopia (no green cones) | #14417E | 0.014 |
| Tritanopia (no blue cones) | #00535B | 0.085 |
| Achromatopsia (no color) | #454545 | 0.109 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1B457F
#1B457F
oklch(39.4% 0.109 257.3)
- #5E3F00
#5E3F00
oklch(39.3% 0.082 77.3)
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 #1B457F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.016
- Cobalt #1E488F ΔE 0.028
- Light Navy #155084 ΔE 0.032
- Deep Sea Blue #015482 ΔE 0.044
- Dusk Blue #26538D ΔE 0.047
- Marine Blue #01386A ΔE 0.056
- Dark Slate Blue #483D8B ΔE 0.063
- Dark Grey Blue #29465B ΔE 0.063
Use #1B457F 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.