#2178B8
Closest named color: Nice Blue (#107AB0). oklch(55.4% 0.127 245.9), rgb(33, 120, 184).
Aa
White text reads best on this color (4.72:1).
About this color
#2178B8 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.127 and its hue 246°. Its hue sits on the cool side of the wheel. The nearest named color is Nice Blue (#107AB0), ΔE 0.017 away. White text reads best on it, at 4.72:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.127) |
| Temperature | cool |
| Nearest name | Nice Blue (#107AB0) |
| Black text | 4.44:1 |
| White text | 4.72:1 |
Values
| HEX | #2178B8 |
| RGB | rgb(33, 120, 184) |
| HSL | hsl(205, 70%, 43%) |
| OKLCH | oklch(55.4% 0.127 245.9) |
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 #2178B8 | 4.72:1 | AA | Lc -77.8 | Fine for body text |
| Black text on #2178B8 | 4.44:1 | AA large text | Lc 31.7 | Non-text elements, placeholder text |
| #2178B8 text on white | 4.72:1 | AA | Lc 72.4 | Content text, not long reading |
| #2178B8 text on black | 4.44:1 | AA large text | Lc -29.3 | Dividers and decoration only |
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
#F1F6FA
oklch(97.1% 0.008 241.7)
-
Step 100
100
#E1EBF5
oklch(93.5% 0.017 248)
-
Step 200
200
#C9DCED
oklch(88.6% 0.031 245.1)
-
Step 300
300
#A3C5E4
oklch(80.9% 0.057 246.1)
-
Step 400
400
#6FA6D6
oklch(70.6% 0.091 245.9)
-
Step 500
500
#468FCC
oklch(63% 0.118 246.4)
-
Step 600
600 (this color)
#2178B8
oklch(55.4% 0.127 245.9)
-
Step 700
700
#12659F
oklch(49.1% 0.118 245.9)
-
Step 800
800
#145381
oklch(42.8% 0.098 245.7)
-
Step 900
900
#194567
oklch(37.7% 0.076 245.2)
-
Step 950
950
#10283D
oklch(26.9% 0.05 247.3)
#2178B8 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) | #5A7BBB | 0.051 |
| Deuteranopia (no green cones) | #446DB7 | 0.036 |
| Tritanopia (no blue cones) | #00888F | 0.091 |
| Achromatopsia (no color) | #737373 | 0.127 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2178B8
#2178B8
oklch(55.4% 0.127 245.9)
- #A36100
#A36100
oklch(55.4% 0.124 65.4)
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 #2178B8, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Nice Blue #107AB0 ΔE 0.017
- Windows Blue #3778BF ΔE 0.019
- Flat Blue #3C73A8 ΔE 0.029
- Mid Blue #276AB3 ΔE 0.039
- French Blue #436BAD ΔE 0.040
- Muted Blue #3B719F ΔE 0.041
- Steel Blue #4682B4 ΔE 0.044
- Water Blue #0E87CC ΔE 0.047
Use #2178B8 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.