#3788BC
Closest named color: Cool Blue (#4984B8). oklch(60% 0.111 240.5), rgb(55, 136, 188).
Aa
Black text reads best on this color (5.41:1).
About this color
#3788BC is a medium-dark, moderately saturated blue. In OKLCH its lightness is 60%, its chroma 0.111 and its hue 241°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.016 away. Black text reads best on it, at 5.41:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | moderately saturated (0.111) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.41:1 |
| White text | 3.88:1 |
Values
| HEX | #3788BC |
| RGB | rgb(55, 136, 188) |
| HSL | hsl(203, 55%, 48%) |
| OKLCH | oklch(60% 0.111 240.5) |
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 #3788BC | 3.88:1 | AA large text | Lc -71.5 | Content text, not long reading |
| Black text on #3788BC | 5.41:1 | AA | Lc 38.1 | Non-text elements, placeholder text |
| #3788BC text on white | 3.88:1 | AA large text | Lc 66.0 | Content text, not long reading |
| #3788BC text on black | 5.41:1 | AA | Lc -35.7 | 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 500.
-
Step 50
50
#F1F6FA
oklch(97.1% 0.008 241.7)
-
Step 100
100
#E1EBF4
oklch(93.5% 0.016 245.1)
-
Step 200
200
#C8DCEC
oklch(88.4% 0.031 242)
-
Step 300
300
#A2C6E1
oklch(80.9% 0.054 240.8)
-
Step 400
400
#6DA8D2
oklch(70.7% 0.087 240.6)
-
Step 500
500 (this color)
#3788BC
oklch(60% 0.111 240.5)
-
Step 600
600
#187BB3
oklch(55.7% 0.121 240.6)
-
Step 700
700
#03679A
oklch(49.1% 0.113 240.8)
-
Step 800
800
#0D547D
oklch(42.7% 0.094 241.1)
-
Step 900
900
#164664
oklch(37.7% 0.072 240.3)
-
Step 950
950
#0F293B
oklch(27% 0.046 241.6)
#3788BC 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) | #7088BE | 0.057 |
| Deuteranopia (no green cones) | #5E7CBB | 0.046 |
| Tritanopia (no blue cones) | #00959A | 0.077 |
| Achromatopsia (no color) | #818181 | 0.111 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3788BC
#3788BC
oklch(60% 0.111 240.5)
- #B06F33
#B06F33
oklch(60% 0.111 60.6)
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 #3788BC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.016
- Steel Blue #4682B4 ΔE 0.020
- Blue NCS #118AB2 ΔE 0.026
- Water Blue #0E87CC ΔE 0.030
- Off Blue #5684AE ΔE 0.031
- Dusty Blue #5A86AD ΔE 0.036
- Faded Blue #658CBB ΔE 0.046
- Windows Blue #3778BF ΔE 0.047
Use #3788BC 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.