#555AB1
Closest named color: Iris (#6258C4). oklch(50.8% 0.136 277.9), rgb(85, 90, 177).
Aa
White text reads best on this color (6.02:1).
About this color
#555AB1 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 51%, its chroma 0.136 and its hue 278°. Its hue sits on the cool side of the wheel. The nearest named color is Iris (#6258C4), ΔE 0.036 away. White text reads best on it, at 6.02:1.
| Hue family | Blues |
| Lightness | medium-dark (51%) |
| Chroma | moderately saturated (0.136) |
| Temperature | cool |
| Nearest name | Iris (#6258C4) |
| Black text | 3.48:1 |
| White text | 6.02:1 |
Values
| HEX | #555AB1 |
| RGB | rgb(85, 90, 177) |
| HSL | hsl(237, 37%, 51%) |
| OKLCH | oklch(50.8% 0.136 277.9) |
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 #555AB1 | 6.02:1 | AA | Lc -85.1 | Fine for body text |
| Black text on #555AB1 | 3.48:1 | AA large text | Lc 24.1 | Dividers and decoration only |
| #555AB1 text on white | 6.02:1 | AA | Lc 79.9 | Fine for body text |
| #555AB1 text on black | 3.48:1 | AA large text | Lc -21.9 | 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
#F4F5FB
oklch(97.1% 0.008 278.6)
-
Step 100
100
#E6E9F7
oklch(93.6% 0.019 276.3)
-
Step 200
200
#D3D7F2
oklch(88.4% 0.037 278.9)
-
Step 300
300
#B6BDEB
oklch(80.9% 0.065 278.1)
-
Step 400
400
#919AE2
oklch(70.7% 0.106 277.9)
-
Step 500
500
#777FD9
oklch(63% 0.135 277.9)
-
Step 600
600
#6167C6
oklch(55.6% 0.145 277.8)
-
Step 700
700 (this color)
#555AB1
oklch(50.8% 0.136 277.9)
-
Step 800
800
#42468B
oklch(42.7% 0.112 278)
-
Step 900
900
#373B6F
oklch(37.6% 0.088 277.9)
-
Step 950
950
#202341
oklch(27% 0.056 277.7)
#555AB1 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) | #3267B4 | 0.048 |
| Deuteranopia (no green cones) | #285FAF | 0.050 |
| Tritanopia (no blue cones) | #2E6D7D | 0.119 |
| Achromatopsia (no color) | #636363 | 0.136 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #555AB1
#555AB1
oklch(50.8% 0.136 277.9)
- #766500
#766500
oklch(50.8% 0.105 97.6)
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 #555AB1, closest first.
No curated palette has a color within ΔE 0.04 of #555AB1.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Iris #6258C4 ΔE 0.036
- French Blue #436BAD ΔE 0.050
- Slate Blue #6A5ACD ΔE 0.054
- Dusky Blue #475F94 ΔE 0.055
- Dark Periwinkle #665FD1 ΔE 0.057
- Mid Blue #276AB3 ΔE 0.058
- Light Indigo #6D5ACF ΔE 0.060
- Denim Blue #3B5B92 ΔE 0.062
Use #555AB1 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.