#217ADA
Closest named color: Windows Blue (#3778BF). oklch(58% 0.168 254.3), rgb(33, 122, 218).
Aa
Black text reads best on this color (4.86:1).
About this color
#217ADA is a medium-dark, vivid blue. In OKLCH its lightness is 58%, its chroma 0.168 and its hue 254°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.042 away. Black text reads best on it, at 4.86:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | vivid (0.168) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.86:1 |
| White text | 4.32:1 |
Values
| HEX | #217ADA |
| RGB | rgb(33, 122, 218) |
| HSL | hsl(211, 74%, 49%) |
| OKLCH | oklch(58% 0.168 254.3) |
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 #217ADA | 4.32:1 | AA large text | Lc -74.9 | Content text, not long reading |
| Black text on #217ADA | 4.86:1 | AA | Lc 34.7 | Non-text elements, placeholder text |
| #217ADA text on white | 4.32:1 | AA large text | Lc 69.4 | Content text, not long reading |
| #217ADA text on black | 4.86:1 | AA | Lc -32.3 | 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
#E0EBF9
oklch(93.6% 0.022 254.4)
-
Step 200
200
#C7DBF5
oklch(88.5% 0.042 255)
-
Step 300
300
#9FC4F1
oklch(80.9% 0.075 253.6)
-
Step 400
400
#6AA3EA
oklch(70.6% 0.121 254.6)
-
Step 500
500
#3E8BE4
oklch(63.2% 0.154 254.1)
-
Step 600
600 (this color)
#217ADA
oklch(58% 0.168 254.3)
-
Step 700
700
#035FB6
oklch(49% 0.157 254.4)
-
Step 800
800
#0B4E93
oklch(42.6% 0.129 254.3)
-
Step 900
900
#144275
oklch(37.7% 0.1 253.9)
-
Step 950
950
#0E2745
oklch(27.1% 0.064 254.6)
#217ADA 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) | #4782DE | 0.037 |
| Deuteranopia (no green cones) | #1E72D8 | 0.022 |
| Tritanopia (no blue cones) | #00919F | 0.125 |
| Achromatopsia (no color) | #7A7A7A | 0.168 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #217ADA
#217ADA
oklch(58% 0.168 254.3)
- #A56D00
#A56D00
oklch(58% 0.123 73.7)
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 #217ADA, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.042
- Water Blue #0E87CC ΔE 0.045
- Cerulean Blue #056EEE ΔE 0.047
- Royal Blue #4169E1 ΔE 0.047
- Clear Blue #247AFD ΔE 0.053
- Dark Sky Blue #448EE4 ΔE 0.063
- Nice Blue #107AB0 ΔE 0.067
- Mid Blue #276AB3 ΔE 0.069
Use #217ADA 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.