#155BA3
Closest named color: Dusk Blue (#26538D). oklch(47% 0.134 253.5), rgb(21, 91, 163).
Aa
White text reads best on this color (6.86:1).
About this color
#155BA3 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 47%, its chroma 0.134 and its hue 254°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.039 away. White text reads best on it, at 6.86:1.
| Hue family | Blues |
| Lightness | medium-dark (47%) |
| Chroma | moderately saturated (0.134) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 3.05:1 |
| White text | 6.86:1 |
Values
| HEX | #155BA3 |
| RGB | rgb(21, 91, 163) |
| HSL | hsl(210, 77%, 36%) |
| OKLCH | oklch(47% 0.134 253.5) |
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 #155BA3 | 6.86:1 | AA | Lc -88.2 | Fine for body text |
| Black text on #155BA3 | 3.05:1 | AA large text | Lc 20.8 | Dividers and decoration only |
| #155BA3 text on white | 6.86:1 | AA | Lc 83.2 | Fine for body text |
| #155BA3 text on black | 3.05:1 | AA large text | Lc -18.7 | 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 700.
-
Step 50
50
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#E1EBF6
oklch(93.6% 0.018 250.6)
-
Step 200
200
#C9DBF1
oklch(88.5% 0.036 253.5)
-
Step 300
300
#A4C4EA
oklch(81% 0.064 253)
-
Step 400
400
#72A4E0
oklch(70.7% 0.103 253.6)
-
Step 500
500
#4B8CD7
oklch(63.1% 0.132 253.5)
-
Step 600
600
#2B74C4
oklch(55.5% 0.143 253.6)
-
Step 700
700 (this color)
#155BA3
oklch(47% 0.134 253.5)
-
Step 800
800
#1B5089
oklch(42.8% 0.11 253.2)
-
Step 900
900
#1C436E
oklch(37.8% 0.086 253)
-
Step 950
950
#122740
oklch(26.9% 0.054 254)
#155BA3 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) | #3561A6 | 0.032 |
| Deuteranopia (no green cones) | #1855A2 | 0.017 |
| Tritanopia (no blue cones) | #006C77 | 0.099 |
| Achromatopsia (no color) | #5A5A5A | 0.134 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #155BA3
#155BA3
oklch(47% 0.134 253.5)
- #7C5100
#7C5100
oklch(47.1% 0.1 73.9)
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 #155BA3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.039
- Denim Blue #3B5B92 ΔE 0.039
- Peacock Blue #016795 ΔE 0.045
- Light Navy Blue #2E5A88 ΔE 0.045
- Mid Blue #276AB3 ΔE 0.050
- Dusky Blue #475F94 ΔE 0.053
- Light Navy #155084 ΔE 0.056
- Denim #3B638C ΔE 0.057
Use #155BA3 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.