#555CB5
Closest named color: Iris (#6258C4). oklch(51.4% 0.139 277), rgb(85, 92, 181).
Aa
White text reads best on this color (5.85:1).
About this color
#555CB5 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 51%, its chroma 0.139 and its hue 277°. Its hue sits on the cool side of the wheel. The nearest named color is Iris (#6258C4), ΔE 0.032 away. White text reads best on it, at 5.85:1.
| Hue family | Blues |
| Lightness | medium-dark (51%) |
| Chroma | moderately saturated (0.139) |
| Temperature | cool |
| Nearest name | Iris (#6258C4) |
| Black text | 3.58:1 |
| White text | 5.85:1 |
Values
| HEX | #555CB5 |
| RGB | rgb(85, 92, 181) |
| HSL | hsl(236, 39%, 52%) |
| OKLCH | oklch(51.4% 0.139 277) |
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 #555CB5 | 5.85:1 | AA | Lc -84.3 | Fine for body text |
| Black text on #555CB5 | 3.58:1 | AA large text | Lc 25.0 | Dividers and decoration only |
| #555CB5 text on white | 5.85:1 | AA | Lc 79.1 | Fine for body text |
| #555CB5 text on black | 3.58:1 | AA large text | Lc -22.7 | 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
#F4F5FC
oklch(97.1% 0.009 279.7)
-
Step 100
100
#E6E9F7
oklch(93.6% 0.019 276.3)
-
Step 200
200
#D2D7F2
oklch(88.4% 0.037 277.3)
-
Step 300
300
#B5BDEC
oklch(80.8% 0.067 277.2)
-
Step 400
400
#909AE3
oklch(70.7% 0.107 277.3)
-
Step 500
500
#757FDB
oklch(63% 0.138 277)
-
Step 600
600
#5F67C8
oklch(55.6% 0.148 276.9)
-
Step 700
700 (this color)
#555CB5
oklch(51.4% 0.139 277)
-
Step 800
800
#40468C
oklch(42.6% 0.114 276.7)
-
Step 900
900
#363B70
oklch(37.6% 0.09 277.1)
-
Step 950
950
#202342
oklch(27% 0.057 277.6)
#555CB5 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) | #3269B8 | 0.047 |
| Deuteranopia (no green cones) | #2761B3 | 0.049 |
| Tritanopia (no blue cones) | #2A7080 | 0.122 |
| Achromatopsia (no color) | #656565 | 0.139 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #555CB5
#555CB5
oklch(51.4% 0.139 277)
- #796700
#796700
oklch(51.6% 0.106 97.1)
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 #555CB5, closest first.
No curated palette has a color within ΔE 0.04 of #555CB5.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Iris #6258C4 ΔE 0.032
- French Blue #436BAD ΔE 0.047
- Slate Blue #6A5ACD ΔE 0.049
- Dark Periwinkle #665FD1 ΔE 0.051
- Light Indigo #6D5ACF ΔE 0.055
- Mid Blue #276AB3 ΔE 0.056
- Dusky Blue #475F94 ΔE 0.059
- Warm Blue #4B57DB ΔE 0.063
Use #555CB5 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.