#155DA3
Closest named color: Denim Blue (#3B5B92). oklch(47.5% 0.131 252.5), rgb(21, 93, 163).
Aa
White text reads best on this color (6.71:1).
About this color
#155DA3 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 47%, its chroma 0.131 and its hue 252°. Its hue sits on the cool side of the wheel. The nearest named color is Denim Blue (#3B5B92), ΔE 0.038 away. White text reads best on it, at 6.71:1.
| Hue family | Blues |
| Lightness | medium-dark (47%) |
| Chroma | moderately saturated (0.131) |
| Temperature | cool |
| Nearest name | Denim Blue (#3B5B92) |
| Black text | 3.12:1 |
| White text | 6.71:1 |
Values
| HEX | #155DA3 |
| RGB | rgb(21, 93, 163) |
| HSL | hsl(210, 77%, 36%) |
| OKLCH | oklch(47.5% 0.131 252.5) |
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 #155DA3 | 6.71:1 | AA | Lc -87.7 | Fine for body text |
| Black text on #155DA3 | 3.12:1 | AA large text | Lc 21.4 | Dividers and decoration only |
| #155DA3 text on white | 6.71:1 | AA | Lc 82.6 | Fine for body text |
| #155DA3 text on black | 3.12:1 | AA large text | Lc -19.3 | 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
#C9DBF0
oklch(88.4% 0.035 252.3)
-
Step 300
300
#A4C4E9
oklch(80.9% 0.063 252.3)
-
Step 400
400
#71A4DF
oklch(70.6% 0.103 252.8)
-
Step 500
500
#4A8CD5
oklch(63% 0.13 252.6)
-
Step 600
600
#2A75C3
oklch(55.6% 0.141 252.6)
-
Step 700
700 (this color)
#155DA3
oklch(47.5% 0.131 252.5)
-
Step 800
800
#1A5088
oklch(42.7% 0.108 252.6)
-
Step 900
900
#1C436D
oklch(37.7% 0.085 252.5)
-
Step 950
950
#112740
oklch(26.9% 0.055 253.1)
#155DA3 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) | #3962A6 | 0.033 |
| Deuteranopia (no green cones) | #1F56A2 | 0.019 |
| Tritanopia (no blue cones) | #006E78 | 0.097 |
| Achromatopsia (no color) | #5C5C5C | 0.131 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #155DA3
#155DA3
oklch(47.5% 0.131 252.5)
- #7E5100
#7E5100
oklch(47.4% 0.101 72.5)
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 #155DA3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Denim Blue #3B5B92 ΔE 0.038
- Peacock Blue #016795 ΔE 0.041
- Dusk Blue #26538D ΔE 0.041
- Light Navy Blue #2E5A88 ΔE 0.045
- Mid Blue #276AB3 ΔE 0.045
- Dusky Blue #475F94 ΔE 0.050
- Denim #3B638C ΔE 0.053
- Deep Sea Blue #015482 ΔE 0.059
Use #155DA3 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.