#2178B7
Closest named color: Nice Blue (#107AB0). oklch(55.4% 0.126 245.5), rgb(33, 120, 183).
Aa
White text reads best on this color (4.73:1).
About this color
#2178B7 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.126 and its hue 245°. Its hue sits on the cool side of the wheel. The nearest named color is Nice Blue (#107AB0), ΔE 0.015 away. White text reads best on it, at 4.73:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.126) |
| Temperature | cool |
| Nearest name | Nice Blue (#107AB0) |
| Black text | 4.43:1 |
| White text | 4.73:1 |
Values
| HEX | #2178B7 |
| RGB | rgb(33, 120, 183) |
| HSL | hsl(205, 69%, 42%) |
| OKLCH | oklch(55.4% 0.126 245.5) |
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 #2178B7 | 4.73:1 | AA | Lc -77.9 | Fine for body text |
| Black text on #2178B7 | 4.43:1 | AA large text | Lc 31.6 | Non-text elements, placeholder text |
| #2178B7 text on white | 4.73:1 | AA | Lc 72.5 | Content text, not long reading |
| #2178B7 text on black | 4.43:1 | AA large text | Lc -29.2 | 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
#E1EBF4
oklch(93.5% 0.016 245.1)
-
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
#6FA7D6
oklch(70.8% 0.091 244.9)
-
Step 500
500
#4690CB
oklch(63.2% 0.116 245.2)
-
Step 600
600 (this color)
#2178B7
oklch(55.4% 0.126 245.5)
-
Step 700
700
#12659E
oklch(49% 0.117 245.5)
-
Step 800
800
#145380
oklch(42.7% 0.096 245.1)
-
Step 900
900
#194567
oklch(37.7% 0.076 245.2)
-
Step 950
950
#10283C
oklch(26.8% 0.048 246)
#2178B7 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) | #5A7BBA | 0.051 |
| Deuteranopia (no green cones) | #456DB6 | 0.037 |
| Tritanopia (no blue cones) | #00878F | 0.088 |
| Achromatopsia (no color) | #737373 | 0.126 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2178B7
#2178B7
oklch(55.4% 0.126 245.5)
- #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 #2178B7, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Nice Blue #107AB0 ΔE 0.015
- Windows Blue #3778BF ΔE 0.020
- Flat Blue #3C73A8 ΔE 0.028
- Mid Blue #276AB3 ΔE 0.039
- Muted Blue #3B719F ΔE 0.040
- French Blue #436BAD ΔE 0.040
- Steel Blue #4682B4 ΔE 0.043
- Ocean Blue #03719C ΔE 0.047
Use #2178B7 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.