#278DB8
Closest named color: Blue NCS (#118AB2). oklch(60.6% 0.11 231.4), rgb(39, 141, 184).
Aa
Black text reads best on this color (5.58:1).
About this color
#278DB8 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 61%, its chroma 0.110 and its hue 231°. Its hue sits on the cool side of the wheel. The nearest named color is Blue NCS (#118AB2), ΔE 0.015 away. Black text reads best on it, at 5.58:1.
| Hue family | Blues |
| Lightness | medium-dark (61%) |
| Chroma | moderately saturated (0.110) |
| Temperature | cool |
| Nearest name | Blue NCS (#118AB2) |
| Black text | 5.58:1 |
| White text | 3.75:1 |
Values
| HEX | #278DB8 |
| RGB | rgb(39, 141, 184) |
| HSL | hsl(198, 65%, 44%) |
| OKLCH | oklch(60.6% 0.11 231.4) |
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 #278DB8 | 3.75:1 | AA large text | Lc -70.2 | Content text, not long reading |
| Black text on #278DB8 | 5.58:1 | AA | Lc 39.3 | Non-text elements, placeholder text |
| #278DB8 text on white | 3.75:1 | AA large text | Lc 64.7 | Content text, not long reading |
| #278DB8 text on black | 5.58:1 | AA | Lc -36.9 | 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
#F1F6F9
oklch(97% 0.007 233.6)
-
Step 100
100
#E0ECF3
oklch(93.6% 0.016 233)
-
Step 200
200
#C6DDEA
oklch(88.4% 0.03 232.5)
-
Step 300
300
#9EC8DE
oklch(81% 0.054 231.1)
-
Step 400
400
#65AACD
oklch(70.6% 0.087 231.9)
-
Step 500
500 (this color)
#278DB8
oklch(60.6% 0.11 231.4)
-
Step 600
600
#007EA9
oklch(55.6% 0.112 231.2)
-
Step 700
700
#006A8F
oklch(49.2% 0.1 231.3)
-
Step 800
800
#005776
oklch(42.8% 0.087 231.2)
-
Step 900
900
#094861
oklch(37.8% 0.072 231.3)
-
Step 950
950
#0A2A39
oklch(27% 0.046 232.6)
#278DB8 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) | #778BBA | 0.073 |
| Deuteranopia (no green cones) | #647EB7 | 0.062 |
| Tritanopia (no blue cones) | #00999B | 0.066 |
| Achromatopsia (no color) | #848484 | 0.110 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #278DB8
#278DB8
oklch(60.6% 0.11 231.4)
- #B66D40
#B66D40
oklch(60.6% 0.111 51)
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 #278DB8, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blue NCS #118AB2 ΔE 0.015
- Cool Blue #4984B8 ΔE 0.032
- Steel Blue #4682B4 ΔE 0.034
- Off Blue #5684AE ΔE 0.040
- Water Blue #0E87CC ΔE 0.040
- Dusty Blue #5A86AD ΔE 0.041
- Teal Blue #01889F ΔE 0.043
- Faded Blue #658CBB ΔE 0.052
Use #278DB8 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.