#1551AC
Closest named color: Cobalt (#1E488F). oklch(45.4% 0.158 259.4), rgb(21, 81, 172).
Aa
White text reads best on this color (7.48:1).
About this color
#1551AC is a medium-dark, vivid blue. In OKLCH its lightness is 45%, its chroma 0.158 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.051 away. White text reads best on it, at 7.48:1.
| Hue family | Blues |
| Lightness | medium-dark (45%) |
| Chroma | vivid (0.158) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.80:1 |
| White text | 7.48:1 |
Values
| HEX | #1551AC |
| RGB | rgb(21, 81, 172) |
| HSL | hsl(216, 78%, 38%) |
| OKLCH | oklch(45.4% 0.158 259.4) |
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 #1551AC | 7.48:1 | AAA | Lc -90.3 | Preferred for body text |
| Black text on #1551AC | 2.80:1 | Fails | Lc 18.6 | Dividers and decoration only |
| #1551AC text on white | 7.48:1 | AAA | Lc 85.4 | Fine for body text |
| #1551AC text on black | 2.80:1 | Fails | Lc -16.6 | Dividers and decoration only |
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
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E0EBFC
oklch(93.7% 0.026 259)
-
Step 200
200
#C5DBFC
oklch(88.6% 0.051 258.4)
-
Step 300
300
#9DC2FD
oklch(80.9% 0.093 259.6)
-
Step 400
400
#67A0FB
oklch(70.7% 0.147 259.4)
-
Step 500
500
#3B85F9
oklch(63.1% 0.188 259.3)
-
Step 600
600
#156BE8
oklch(55.6% 0.205 259.3)
-
Step 700
700
#0458CA
oklch(49.1% 0.191 259.4)
-
Step 800
800 (this color)
#1551AC
oklch(45.4% 0.158 259.4)
-
Step 900
900
#133E81
oklch(37.6% 0.123 259.4)
-
Step 950
950
#0D254C
oklch(27% 0.078 259.7)
#1551AC 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) | #0B5CAF | 0.029 |
| Deuteranopia (no green cones) | #004EAA | 0.013 |
| Tritanopia (no blue cones) | #006776 | 0.120 |
| Achromatopsia (no color) | #555555 | 0.158 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1551AC
#1551AC
oklch(45.4% 0.158 259.4)
- #724F00
#724F00
oklch(45.4% 0.094 79.2)
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 #1551AC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.051
- Dusk Blue #26538D ΔE 0.052
- Blue Blue #2242C7 ΔE 0.055
- Sapphire #2138AB ΔE 0.059
- Denim Blue #3B5B92 ΔE 0.064
- Light Navy #155084 ΔE 0.066
- Blueberry #464196 ΔE 0.066
- Light Navy Blue #2E5A88 ΔE 0.070
Use #1551AC 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.