#647BCB
Closest named color: Cool Blue (#4984B8). oklch(60.1% 0.125 270.2), rgb(100, 123, 203).
Aa
Black text reads best on this color (5.23:1).
About this color
#647BCB is a medium-dark, moderately saturated blue. In OKLCH its lightness is 60%, its chroma 0.125 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.051 away. Black text reads best on it, at 5.23:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | moderately saturated (0.125) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.23:1 |
| White text | 4.00:1 |
Values
| HEX | #647BCB |
| RGB | rgb(100, 123, 203) |
| HSL | hsl(227, 50%, 59%) |
| OKLCH | oklch(60.1% 0.125 270.2) |
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 #647BCB | 4.00:1 | AA large text | Lc -72.8 | Content text, not long reading |
| Black text on #647BCB | 5.23:1 | AA | Lc 36.8 | Non-text elements, placeholder text |
| #647BCB text on white | 4.00:1 | AA large text | Lc 67.3 | Content text, not long reading |
| #647BCB text on black | 5.23:1 | AA | Lc -34.4 | Non-text elements, placeholder text |
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 500.
-
Step 50
50
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E5EAF6
oklch(93.7% 0.017 267.8)
-
Step 200
200
#D0D9F0
oklch(88.6% 0.033 268.7)
-
Step 300
300
#B1BFE9
oklch(80.8% 0.061 270.5)
-
Step 400
400
#899EDE
oklch(70.8% 0.097 269.9)
-
Step 500
500 (this color)
#647BCB
oklch(60.1% 0.125 270.2)
-
Step 600
600
#556CC2
oklch(55.5% 0.136 270.2)
-
Step 700
700
#465AA8
oklch(49.2% 0.127 270.4)
-
Step 800
800
#394A88
oklch(42.7% 0.105 270)
-
Step 900
900
#313E6D
oklch(37.7% 0.082 270.4)
-
Step 950
950
#1D2540
oklch(27.1% 0.052 270.2)
#647BCB 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) | #5B84CE | 0.024 |
| Deuteranopia (no green cones) | #507BC9 | 0.024 |
| Tritanopia (no blue cones) | #378C99 | 0.112 |
| Achromatopsia (no color) | #7F7F7F | 0.125 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #647BCB
#647BCB
oklch(60.1% 0.125 270.2)
- #9D7C00
#9D7C00
oklch(60.1% 0.123 90)
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 #647BCB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.051
- Windows Blue #3778BF ΔE 0.053
- Soft Blue #6488EA ΔE 0.053
- Steel Blue #4682B4 ΔE 0.055
- Faded Blue #658CBB ΔE 0.059
- Off Blue #5684AE ΔE 0.059
- Dark Sky Blue #448EE4 ΔE 0.060
- Dusty Blue #5A86AD ΔE 0.063
Use #647BCB 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.