#2173DD
Closest named color: Cerulean Blue (#056EEE). oklch(56.7% 0.179 257.1), rgb(33, 115, 221).
Aa
White text reads best on this color (4.60:1).
About this color
#2173DD is a medium-dark, vivid blue. In OKLCH its lightness is 57%, its chroma 0.179 and its hue 257°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean Blue (#056EEE), ΔE 0.031 away. White text reads best on it, at 4.60:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | vivid (0.179) |
| Temperature | cool |
| Nearest name | Cerulean Blue (#056EEE) |
| Black text | 4.56:1 |
| White text | 4.60:1 |
Values
| HEX | #2173DD |
| RGB | rgb(33, 115, 221) |
| HSL | hsl(214, 74%, 50%) |
| OKLCH | oklch(56.7% 0.179 257.1) |
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 #2173DD | 4.60:1 | AA | Lc -76.9 | Fine for body text |
| Black text on #2173DD | 4.56:1 | AA | Lc 32.7 | Non-text elements, placeholder text |
| #2173DD text on white | 4.60:1 | AA | Lc 71.4 | Content text, not long reading |
| #2173DD text on black | 4.56:1 | AA | Lc -30.3 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E0EBFA
oklch(93.6% 0.024 256.1)
-
Step 200
200
#C7DBF7
oklch(88.5% 0.044 256.8)
-
Step 300
300
#A0C3F5
oklch(80.9% 0.081 257.3)
-
Step 400
400
#6BA2F0
oklch(70.7% 0.129 257.2)
-
Step 500
500
#4188EB
oklch(63.1% 0.165 257.3)
-
Step 600
600 (this color)
#2173DD
oklch(56.7% 0.179 257.1)
-
Step 700
700
#0D5DBC
oklch(49.1% 0.166 256.9)
-
Step 800
800
#104C98
oklch(42.6% 0.138 257.1)
-
Step 900
900
#164079
oklch(37.6% 0.108 257.2)
-
Step 950
950
#0E2647
oklch(27% 0.068 257.1)
#2173DD 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) | #347EE1 | 0.034 |
| Deuteranopia (no green cones) | #006DDB | 0.021 |
| Tritanopia (no blue cones) | #008D9D | 0.137 |
| Achromatopsia (no color) | #757575 | 0.179 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2173DD
#2173DD
oklch(56.7% 0.179 257.1)
- #9D6C00
#9D6C00
oklch(56.8% 0.119 77.4)
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 #2173DD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean Blue #056EEE ΔE 0.031
- Royal Blue #4169E1 ΔE 0.032
- Clear Blue #247AFD ΔE 0.051
- Windows Blue #3778BF ΔE 0.052
- Neon Blue #4361EE ΔE 0.055
- Azul #1D5DEC ΔE 0.060
- Bright Blue #0165FC ΔE 0.061
- Water Blue #0E87CC ΔE 0.064
Use #2173DD 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.