#647BBD
Closest named color: Cool Blue (#4984B8). oklch(59.3% 0.105 268.5), rgb(100, 123, 189).
Aa
Black text reads best on this color (5.10:1).
About this color
#647BBD is a medium-dark, moderately saturated blue. In OKLCH its lightness is 59%, its chroma 0.105 and its hue 269°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.039 away. Black text reads best on it, at 5.10:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.105) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.10:1 |
| White text | 4.10:1 |
Values
| HEX | #647BBD |
| RGB | rgb(100, 123, 189) |
| HSL | hsl(224, 40%, 57%) |
| OKLCH | oklch(59.3% 0.105 268.5) |
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 #647BBD | 4.10:1 | AA large text | Lc -73.6 | Content text, not long reading |
| Black text on #647BBD | 5.10:1 | AA | Lc 35.9 | Non-text elements, placeholder text |
| #647BBD text on white | 4.10:1 | AA large text | Lc 68.1 | Content text, not long reading |
| #647BBD text on black | 5.10:1 | AA | Lc -33.5 | 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 600.
-
Step 50
50
#F4F5FA
oklch(97.1% 0.007 277.2)
-
Step 100
100
#E6EAF3
oklch(93.7% 0.013 266.7)
-
Step 200
200
#D2D9EB
oklch(88.5% 0.026 268.8)
-
Step 300
300
#B4C0E0
oklch(80.9% 0.047 269.1)
-
Step 400
400
#8D9FD1
oklch(70.7% 0.076 269.1)
-
Step 500
500
#7187C4
oklch(63.1% 0.096 268.4)
-
Step 600
600 (this color)
#647BBD
oklch(59.3% 0.105 268.5)
-
Step 700
700
#495D98
oklch(49% 0.098 268.5)
-
Step 800
800
#3C4C7B
oklch(42.6% 0.081 268.6)
-
Step 900
900
#334063
oklch(37.7% 0.063 267.8)
-
Step 950
950
#1E263A
oklch(27.1% 0.039 267.1)
#647BBD 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) | #6381C0 | 0.016 |
| Deuteranopia (no green cones) | #5A7ABC | 0.013 |
| Tritanopia (no blue cones) | #428993 | 0.094 |
| Achromatopsia (no color) | #7D7D7D | 0.105 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #647BBD
#647BBD
oklch(59.3% 0.105 268.5)
- #987A28
#987A28
oklch(59.3% 0.105 88.1)
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 #647BBD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.039
- Steel Blue #4682B4 ΔE 0.041
- Off Blue #5684AE ΔE 0.042
- Dusty Blue #5A86AD ΔE 0.046
- Windows Blue #3778BF ΔE 0.049
- Faded Blue #658CBB ΔE 0.049
- Stormy Blue #507B9C ΔE 0.059
- Flat Blue #3C73A8 ΔE 0.062
Use #647BBD 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.