#5B5FCF
Closest named color: Dark Periwinkle (#665FD1). oklch(54.2% 0.17 277.6), rgb(91, 95, 207).
Aa
White text reads best on this color (5.27:1).
About this color
#5B5FCF is a medium-dark, vivid blue. In OKLCH its lightness is 54%, its chroma 0.170 and its hue 278°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Periwinkle (#665FD1), ΔE 0.016 away. White text reads best on it, at 5.27:1.
| Hue family | Blues |
| Lightness | medium-dark (54%) |
| Chroma | vivid (0.170) |
| Temperature | cool |
| Nearest name | Dark Periwinkle (#665FD1) |
| Black text | 3.98:1 |
| White text | 5.27:1 |
Values
| HEX | #5B5FCF |
| RGB | rgb(91, 95, 207) |
| HSL | hsl(238, 55%, 58%) |
| OKLCH | oklch(54.2% 0.17 277.6) |
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 #5B5FCF | 5.27:1 | AA | Lc -81.3 | Fine for body text |
| Black text on #5B5FCF | 3.98:1 | AA large text | Lc 28.2 | Dividers and decoration only |
| #5B5FCF text on white | 5.27:1 | AA | Lc 75.9 | Fine for body text |
| #5B5FCF text on black | 3.98:1 | AA large text | Lc -25.8 | 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
#F3F5FC
oklch(97.1% 0.01 273.4)
-
Step 100
100
#E6E9F9
oklch(93.6% 0.022 277.5)
-
Step 200
200
#D2D7F6
oklch(88.5% 0.043 278.2)
-
Step 300
300
#B4BDF2
oklch(81% 0.076 277.1)
-
Step 400
400
#8E98EC
oklch(70.6% 0.123 277.6)
-
Step 500
500
#747DE6
oklch(63.2% 0.156 277.3)
-
Step 600
600 (this color)
#5B5FCF
oklch(54.2% 0.17 277.6)
-
Step 700
700
#4E51B7
oklch(49% 0.158 277.6)
-
Step 800
800
#404394
oklch(42.6% 0.13 277.7)
-
Step 900
900
#363A76
oklch(37.8% 0.101 277.5)
-
Step 950
950
#1F2245
oklch(26.9% 0.064 277.4)
#5B5FCF 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) | #1771D3 | 0.067 |
| Deuteranopia (no green cones) | #0067CD | 0.069 |
| Tritanopia (no blue cones) | #1B798E | 0.148 |
| Achromatopsia (no color) | #6C6C6C | 0.170 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5B5FCF
#5B5FCF
oklch(54.2% 0.17 277.6)
- #816F00
#816F00
oklch(54.2% 0.112 97.9)
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 #5B5FCF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Periwinkle #665FD1 ΔE 0.016
- Slate Blue #6A5ACD ΔE 0.024
- Iris #6258C4 ΔE 0.024
- Light Indigo #6D5ACF ΔE 0.028
- Warm Blue #4B57DB ΔE 0.036
- Royal Blue #4169E1 ΔE 0.043
- Neon Blue #4361EE ΔE 0.055
- Bluey Purple #6241C7 ΔE 0.066
Use #5B5FCF 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.