#647DB3
Closest named color: Off Blue (#5684AE). oklch(59.3% 0.088 264.8), rgb(100, 125, 179).
Aa
Black text reads best on this color (5.12:1).
About this color
#647DB3 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 59%, its chroma 0.088 and its hue 265°. Its hue sits on the cool side of the wheel. The nearest named color is Off Blue (#5684AE), ΔE 0.027 away. Black text reads best on it, at 5.12:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.088) |
| Temperature | cool |
| Nearest name | Off Blue (#5684AE) |
| Black text | 5.12:1 |
| White text | 4.09:1 |
Values
| HEX | #647DB3 |
| RGB | rgb(100, 125, 179) |
| HSL | hsl(221, 34%, 55%) |
| OKLCH | oklch(59.3% 0.088 264.8) |
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 #647DB3 | 4.09:1 | AA large text | Lc -73.6 | Content text, not long reading |
| Black text on #647DB3 | 5.12:1 | AA | Lc 36.0 | Non-text elements, placeholder text |
| #647DB3 text on white | 4.09:1 | AA large text | Lc 68.1 | Content text, not long reading |
| #647DB3 text on black | 5.12:1 | AA | Lc -33.6 | 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
#F4F5F9
oklch(97.1% 0.005 275)
-
Step 100
100
#E6EAF2
oklch(93.6% 0.012 264.5)
-
Step 200
200
#D2D9E8
oklch(88.4% 0.022 265.8)
-
Step 300
300
#B4C1DB
oklch(80.9% 0.039 264.3)
-
Step 400
400
#8DA1C9
oklch(70.8% 0.063 264)
-
Step 500
500
#7189BB
oklch(63.1% 0.081 264.4)
-
Step 600
600 (this color)
#647DB3
oklch(59.3% 0.088 264.8)
-
Step 700
700
#4A5F8F
oklch(49% 0.082 265.5)
-
Step 800
800
#3C4E74
oklch(42.6% 0.068 264.4)
-
Step 900
900
#34415E
oklch(37.7% 0.053 265.4)
-
Step 950
950
#1E2637
oklch(26.9% 0.034 264.8)
#647DB3 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) | #6A81B5 | 0.014 |
| Deuteranopia (no green cones) | #617AB2 | 0.010 |
| Tritanopia (no blue cones) | #478890 | 0.079 |
| Achromatopsia (no color) | #7D7D7D | 0.088 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #647DB3
#647DB3
oklch(59.3% 0.088 264.8)
- #967A3C
#967A3C
oklch(59.3% 0.088 85.2)
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 #647DB3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Off Blue #5684AE ΔE 0.027
- Dusty Blue #5A86AD ΔE 0.031
- Cool Blue #4984B8 ΔE 0.032
- Steel Blue #4682B4 ΔE 0.033
- Faded Blue #658CBB ΔE 0.041
- Stormy Blue #507B9C ΔE 0.045
- Cerulean #457B9D ΔE 0.052
- Lavender Gray #7E7F9A ΔE 0.053
Use #647DB3 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.