#1805DB
Named color: Ultramarine Blue. oklch(41% 0.274 266.8), rgb(24, 5, 219).
Aa
White text reads best on this color (10.07:1).
About this color
#1805DB is a dark, vivid blue. In OKLCH its lightness is 41%, its chroma 0.274 and its hue 267°. Its hue sits on the cool side of the wheel. It is the named color Ultramarine Blue. White text reads best on it, at 10.07:1.
| Hue family | Blues |
| Lightness | dark (41%) |
| Chroma | vivid (0.274) |
| Temperature | cool |
| Nearest name | Ultramarine Blue |
| Black text | 2.08:1 |
| White text | 10.07:1 |
Values
| HEX | #1805DB |
| RGB | rgb(24, 5, 219) |
| HSL | hsl(245, 96%, 44%) |
| OKLCH | oklch(41% 0.274 266.8) |
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 #1805DB | 10.07:1 | AAA | Lc -94.9 | Preferred for body text |
| Black text on #1805DB | 2.08:1 | Fails | Lc 13.5 | Not readable |
| #1805DB text on white | 10.07:1 | AAA | Lc 90.4 | Preferred for body text |
| #1805DB text on black | 2.08:1 | Fails | Lc -11.9 | 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
#F1F5FF
oklch(97% 0.014 268.5)
-
Step 100
100
#E1EAFF
oklch(93.7% 0.03 267.2)
-
Step 200
200
#C8D9FF
oklch(88.5% 0.056 266.2)
-
Step 300
300
#A5BFFF
oklch(80.9% 0.095 267.2)
-
Step 400
400
#759BFF
oklch(70.6% 0.153 266.8)
-
Step 500
500
#537EFF
oklch(63.1% 0.197 266.8)
-
Step 600
600
#345CFF
oklch(55.5% 0.245 266.9)
-
Step 700
700
#2133FF
oklch(49.1% 0.287 266.8)
-
Step 800
800 (this color)
#1805DB
oklch(41% 0.274 266.8)
-
Step 900
900
#1424B0
oklch(37.7% 0.214 266.8)
-
Step 950
950
#0A1967
oklch(27% 0.136 266.8)
#1805DB 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) | #004CE0 | 0.090 |
| Deuteranopia (no green cones) | #0036D8 | 0.046 |
| Tritanopia (no blue cones) | #005B80 | 0.203 |
| Achromatopsia (no color) | #424242 | 0.276 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1805DB
#1805DB
oklch(41% 0.274 266.8)
- #5E4700
#5E4700
oklch(41.1% 0.084 87.4)
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 #1805DB, closest first.
No curated palette has a color within ΔE 0.04 of #1805DB.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Pure Blue #0203E2 ΔE 0.017
- True Blue #010FCC ΔE 0.028
- Medium Blue #0000CD ΔE 0.031
- Strong Blue #0C06F7 ΔE 0.046
- Primary Blue #0804F9 ΔE 0.049
- Rich Blue #021BF9 ΔE 0.054
- Blue #0000FF ΔE 0.059
- Ultramarine #2000B1 ΔE 0.072
Use #1805DB 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.