#555DDB
Closest named color: Warm Blue (#4B57DB). oklch(54.4% 0.19 275.4), rgb(85, 93, 219).
Aa
White text reads best on this color (5.28:1).
About this color
#555DDB is a medium-dark, vivid blue. In OKLCH its lightness is 54%, its chroma 0.190 and its hue 275°. Its hue sits on the cool side of the wheel. The nearest named color is Warm Blue (#4B57DB), ΔE 0.021 away. White text reads best on it, at 5.28:1.
| Hue family | Blues |
| Lightness | medium-dark (54%) |
| Chroma | vivid (0.190) |
| Temperature | cool |
| Nearest name | Warm Blue (#4B57DB) |
| Black text | 3.97:1 |
| White text | 5.28:1 |
Values
| HEX | #555DDB |
| RGB | rgb(85, 93, 219) |
| HSL | hsl(236, 65%, 60%) |
| OKLCH | oklch(54.4% 0.19 275.4) |
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 #555DDB | 5.28:1 | AA | Lc -81.2 | Fine for body text |
| Black text on #555DDB | 3.97:1 | AA large text | Lc 28.2 | Dividers and decoration only |
| #555DDB text on white | 5.28:1 | AA | Lc 75.8 | Fine for body text |
| #555DDB text on black | 3.97:1 | AA large text | Lc -25.9 | 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 600.
-
Step 50
50
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E5E9FB
oklch(93.6% 0.025 275.9)
-
Step 200
200
#D0D7F9
oklch(88.5% 0.047 276.2)
-
Step 300
300
#B0BDF8
oklch(80.9% 0.085 274.7)
-
Step 400
400
#8998F5
oklch(70.7% 0.137 275.4)
-
Step 500
500
#6E7BF1
oklch(63.1% 0.175 275.5)
-
Step 600
600 (this color)
#555DDB
oklch(54.4% 0.19 275.4)
-
Step 700
700
#494FC2
oklch(49.1% 0.177 275.5)
-
Step 800
800
#3B429D
oklch(42.8% 0.146 275.1)
-
Step 900
900
#32397D
oklch(37.8% 0.114 275.1)
-
Step 950
950
#1D2249
oklch(27% 0.072 275)
#555DDB 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) | #0072DF | 0.068 |
| Deuteranopia (no green cones) | #0066D8 | 0.061 |
| Tritanopia (no blue cones) | #007B93 | 0.160 |
| Achromatopsia (no color) | #6C6C6C | 0.190 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #555DDB
#555DDB
oklch(54.4% 0.19 275.4)
- #846E00
#846E00
oklch(54.3% 0.112 95.1)
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 #555DDB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Warm Blue #4B57DB ΔE 0.021
- Dark Periwinkle #665FD1 ΔE 0.030
- Royal Blue #4169E1 ΔE 0.034
- Neon Blue #4361EE ΔE 0.035
- Slate Blue #6A5ACD ΔE 0.037
- Light Indigo #6D5ACF ΔE 0.039
- Iris #6258C4 ΔE 0.040
- Azul #1D5DEC ΔE 0.058
Use #555DDB 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.