#3F84DB
Closest named color: Dark Sky Blue (#448EE4). oklch(61.1% 0.15 255.6), rgb(63, 132, 219).
Aa
Black text reads best on this color (5.53:1).
About this color
#3F84DB is a medium-dark, vivid blue. In OKLCH its lightness is 61%, its chroma 0.150 and its hue 256°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.029 away. Black text reads best on it, at 5.53:1.
| Hue family | Blues |
| Lightness | medium-dark (61%) |
| Chroma | vivid (0.150) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 5.53:1 |
| White text | 3.79:1 |
Values
| HEX | #3F84DB |
| RGB | rgb(63, 132, 219) |
| HSL | hsl(213, 68%, 55%) |
| OKLCH | oklch(61.1% 0.15 255.6) |
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 #3F84DB | 3.79:1 | AA large text | Lc -70.6 | Content text, not long reading |
| Black text on #3F84DB | 5.53:1 | AA | Lc 38.9 | Non-text elements, placeholder text |
| #3F84DB text on white | 3.79:1 | AA large text | Lc 65.1 | Content text, not long reading |
| #3F84DB text on black | 5.53:1 | AA | Lc -36.5 | 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 500.
-
Step 50
50
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E1EBF8
oklch(93.6% 0.021 254.9)
-
Step 200
200
#C8DBF4
oklch(88.5% 0.04 255.3)
-
Step 300
300
#A2C3F0
oklch(80.9% 0.073 256.2)
-
Step 400
400
#6EA3E8
oklch(70.7% 0.116 255.5)
-
Step 500
500 (this color)
#3F84DB
oklch(61.1% 0.15 255.6)
-
Step 600
600
#2372D0
oklch(55.6% 0.163 255.6)
-
Step 700
700
#155FB4
oklch(49.1% 0.152 255.7)
-
Step 800
800
#154E91
oklch(42.7% 0.125 255.4)
-
Step 900
900
#194274
oklch(37.8% 0.097 255.2)
-
Step 950
950
#102744
oklch(27.1% 0.062 255.3)
#3F84DB 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) | #5B8BDE | 0.035 |
| Deuteranopia (no green cones) | #437CD9 | 0.021 |
| Tritanopia (no blue cones) | #0098A5 | 0.116 |
| Achromatopsia (no color) | #838383 | 0.150 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F84DB
#3F84DB
oklch(61.1% 0.15 255.6)
- #AF7700
#AF7700
oklch(61.2% 0.128 76)
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 #3F84DB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.029
- Water Blue #0E87CC ΔE 0.036
- Soft Blue #6488EA ΔE 0.046
- Windows Blue #3778BF ΔE 0.051
- Chefchaouen Blue #4895EF ΔE 0.053
- Cool Blue #4984B8 ΔE 0.054
- Dodger Blue #1E90FF ΔE 0.058
- Steel Blue #4682B4 ΔE 0.059
Use #3F84DB 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.