#3781EF
Closest named color: Clear Blue (#247AFD). oklch(61.5% 0.181 258.5), rgb(55, 129, 239).
Aa
Black text reads best on this color (5.54:1).
About this color
#3781EF is a medium-dark, vivid blue. In OKLCH its lightness is 62%, its chroma 0.181 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Clear Blue (#247AFD), ΔE 0.032 away. Black text reads best on it, at 5.54:1.
| Hue family | Blues |
| Lightness | medium-dark (62%) |
| Chroma | vivid (0.181) |
| Temperature | cool |
| Nearest name | Clear Blue (#247AFD) |
| Black text | 5.54:1 |
| White text | 3.78:1 |
Values
| HEX | #3781EF |
| RGB | rgb(55, 129, 239) |
| HSL | hsl(216, 85%, 58%) |
| OKLCH | oklch(61.5% 0.181 258.5) |
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 #3781EF | 3.78:1 | AA large text | Lc -70.4 | Content text, not long reading |
| Black text on #3781EF | 5.54:1 | AA | Lc 39.2 | Non-text elements, placeholder text |
| #3781EF text on white | 3.78:1 | AA large text | Lc 64.9 | Content text, not long reading |
| #3781EF text on black | 5.54:1 | AA | Lc -36.8 | 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
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E0EBFB
oklch(93.7% 0.025 257.6)
-
Step 200
200
#C6DBFA
oklch(88.6% 0.048 258)
-
Step 300
300
#9EC2FA
oklch(80.8% 0.089 259.1)
-
Step 400
400
#67A1F8
oklch(70.7% 0.142 258.3)
-
Step 500
500 (this color)
#3781EF
oklch(61.5% 0.181 258.5)
-
Step 600
600
#156DE3
oklch(55.7% 0.196 258.4)
-
Step 700
700
#045AC6
oklch(49.2% 0.183 258.5)
-
Step 800
800
#0B4AA0
oklch(42.7% 0.152 258.6)
-
Step 900
900
#133F7F
oklch(37.7% 0.119 258.5)
-
Step 950
950
#0D254A
oklch(26.9% 0.075 258.9)
#3781EF 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) | #458CF3 | 0.033 |
| Deuteranopia (no green cones) | #127BED | 0.026 |
| Tritanopia (no blue cones) | #009BAC | 0.140 |
| Achromatopsia (no color) | #838383 | 0.181 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3781EF
#3781EF
oklch(61.5% 0.181 258.5)
- #AE7900
#AE7900
oklch(61.4% 0.128 78)
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 #3781EF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Clear Blue #247AFD ΔE 0.032
- Dodger Blue #1E90FF ΔE 0.042
- Dark Sky Blue #448EE4 ΔE 0.043
- Soft Blue #6488EA ΔE 0.049
- Cornflower #6A79F7 ΔE 0.053
- Chefchaouen Blue #4895EF ΔE 0.057
- Cerulean Blue #056EEE ΔE 0.057
- Royal Blue #4169E1 ΔE 0.061
Use #3781EF 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.