#1978CB
Closest named color: Windows Blue (#3778BF). oklch(56.4% 0.152 250.8), rgb(25, 120, 203).
Aa
Black text reads best on this color (4.59:1).
About this color
#1978CB is a medium-dark, vivid blue. In OKLCH its lightness is 56%, its chroma 0.152 and its hue 251°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.024 away. Black text reads best on it, at 4.59:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | vivid (0.152) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.59:1 |
| White text | 4.57:1 |
Values
| HEX | #1978CB |
| RGB | rgb(25, 120, 203) |
| HSL | hsl(208, 78%, 45%) |
| OKLCH | oklch(56.4% 0.152 250.8) |
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 #1978CB | 4.57:1 | AA | Lc -76.7 | Fine for body text |
| Black text on #1978CB | 4.59:1 | AA | Lc 32.9 | Non-text elements, placeholder text |
| #1978CB text on white | 4.57:1 | AA | Lc 71.2 | Content text, not long reading |
| #1978CB text on black | 4.59:1 | AA | Lc -30.4 | 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 600.
-
Step 50
50
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E0EBF7
oklch(93.5% 0.02 250.4)
-
Step 200
200
#C7DCF2
oklch(88.6% 0.038 249.5)
-
Step 300
300
#A0C4EC
oklch(80.8% 0.069 251.4)
-
Step 400
400
#6BA5E3
oklch(70.7% 0.11 251.1)
-
Step 500
500
#3F8DDB
oklch(63.1% 0.141 251)
-
Step 600
600 (this color)
#1978CB
oklch(56.4% 0.152 250.8)
-
Step 700
700
#0162AD
oklch(49.1% 0.142 250.9)
-
Step 800
800
#0A508C
oklch(42.6% 0.118 251)
-
Step 900
900
#144370
oklch(37.6% 0.092 251)
-
Step 950
950
#0E2842
oklch(27.1% 0.058 250.8)
#1978CB 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) | #4E7ECE | 0.044 |
| Deuteranopia (no green cones) | #306EC9 | 0.027 |
| Tritanopia (no blue cones) | #008C97 | 0.112 |
| Achromatopsia (no color) | #757575 | 0.152 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1978CB
#1978CB
oklch(56.4% 0.152 250.8)
- #A26700
#A26700
oklch(56.4% 0.122 70.6)
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 #1978CB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.024
- Water Blue #0E87CC ΔE 0.041
- Nice Blue #107AB0 ΔE 0.044
- Mid Blue #276AB3 ΔE 0.049
- Flat Blue #3C73A8 ΔE 0.055
- French Blue #436BAD ΔE 0.056
- Royal Blue #4169E1 ΔE 0.058
- Steel Blue #4682B4 ΔE 0.059
Use #1978CB 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.