#3F7DD5
Closest named color: Windows Blue (#3778BF). oklch(59.2% 0.149 257.5), rgb(63, 125, 213).
Aa
Black text reads best on this color (5.10:1).
About this color
#3F7DD5 is a medium-dark, vivid blue. In OKLCH its lightness is 59%, its chroma 0.149 and its hue 258°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.036 away. Black text reads best on it, at 5.10:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | vivid (0.149) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 5.10:1 |
| White text | 4.11:1 |
Values
| HEX | #3F7DD5 |
| RGB | rgb(63, 125, 213) |
| HSL | hsl(215, 64%, 54%) |
| OKLCH | oklch(59.2% 0.149 257.5) |
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 #3F7DD5 | 4.11:1 | AA large text | Lc -73.4 | Content text, not long reading |
| Black text on #3F7DD5 | 5.10:1 | AA | Lc 36.1 | Non-text elements, placeholder text |
| #3F7DD5 text on white | 4.11:1 | AA large text | Lc 67.9 | Content text, not long reading |
| #3F7DD5 text on black | 5.10:1 | AA | Lc -33.7 | 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
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E2EBF7
oklch(93.7% 0.019 255.5)
-
Step 200
200
#CADBF2
oklch(88.6% 0.037 256)
-
Step 300
300
#A6C3EC
oklch(81% 0.066 257)
-
Step 400
400
#75A2E3
oklch(70.6% 0.108 257.5)
-
Step 500
500
#518ADB
oklch(63.2% 0.137 257.4)
-
Step 600
600 (this color)
#3F7DD5
oklch(59.2% 0.149 257.5)
-
Step 700
700
#265FAE
oklch(49.1% 0.139 257.5)
-
Step 800
800
#214E8D
oklch(42.8% 0.116 257.5)
-
Step 900
900
#204170
oklch(37.6% 0.09 257.5)
-
Step 950
950
#142742
oklch(27.2% 0.056 257.3)
#3F7DD5 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) | #5385D8 | 0.031 |
| Deuteranopia (no green cones) | #3B77D3 | 0.017 |
| Tritanopia (no blue cones) | #00919E | 0.118 |
| Achromatopsia (no color) | #7D7D7D | 0.149 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F7DD5
#3F7DD5
oklch(59.2% 0.149 257.5)
- #A67300
#A67300
oklch(59.3% 0.124 77.8)
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 #3F7DD5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.036
- Water Blue #0E87CC ΔE 0.039
- Dark Sky Blue #448EE4 ΔE 0.049
- Cool Blue #4984B8 ΔE 0.053
- Steel Blue #4682B4 ΔE 0.056
- Royal Blue #4169E1 ΔE 0.057
- Soft Blue #6488EA ΔE 0.059
- Clear Blue #247AFD ΔE 0.064
Use #3F7DD5 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.