#1584B4
Closest named color: Blue NCS (#118AB2). oklch(57.9% 0.116 234.2), rgb(21, 132, 180).
Aa
Black text reads best on this color (4.99:1).
About this color
#1584B4 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 58%, its chroma 0.116 and its hue 234°. Its hue sits on the cool side of the wheel. The nearest named color is Blue NCS (#118AB2), ΔE 0.019 away. Black text reads best on it, at 4.99:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | moderately saturated (0.116) |
| Temperature | cool |
| Nearest name | Blue NCS (#118AB2) |
| Black text | 4.99:1 |
| White text | 4.20:1 |
Values
| HEX | #1584B4 |
| RGB | rgb(21, 132, 180) |
| HSL | hsl(198, 79%, 39%) |
| OKLCH | oklch(57.9% 0.116 234.2) |
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 #1584B4 | 4.20:1 | AA large text | Lc -74.0 | Content text, not long reading |
| Black text on #1584B4 | 4.99:1 | AA | Lc 35.6 | Non-text elements, placeholder text |
| #1584B4 text on white | 4.20:1 | AA large text | Lc 68.5 | Content text, not long reading |
| #1584B4 text on black | 4.99:1 | AA | Lc -33.1 | 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
#F1F6F9
oklch(97% 0.007 233.6)
-
Step 100
100
#E1ECF3
oklch(93.7% 0.015 235.4)
-
Step 200
200
#C7DDEA
oklch(88.5% 0.03 233.6)
-
Step 300
300
#A0C7DE
oklch(80.9% 0.053 234.2)
-
Step 400
400
#6AA9CD
oklch(70.6% 0.084 234.8)
-
Step 500
500
#3B93C0
oklch(63% 0.107 234.5)
-
Step 600
600 (this color)
#1584B4
oklch(57.9% 0.116 234.2)
-
Step 700
700
#006992
oklch(49.1% 0.103 234.3)
-
Step 800
800
#005678
oklch(42.7% 0.089 233.9)
-
Step 900
900
#114761
oklch(37.7% 0.07 234.5)
-
Step 950
950
#0D2A39
oklch(27.1% 0.044 234.3)
#1584B4 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) | #6C83B6 | 0.071 |
| Deuteranopia (no green cones) | #5875B3 | 0.059 |
| Tritanopia (no blue cones) | #009194 | 0.072 |
| Achromatopsia (no color) | #7B7B7B | 0.116 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1584B4
#1584B4
oklch(57.9% 0.116 234.2)
- #AE652F
#AE652F
oklch(57.9% 0.116 54.3)
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 #1584B4, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blue NCS #118AB2 ΔE 0.019
- Steel Blue #4682B4 ΔE 0.029
- Nice Blue #107AB0 ΔE 0.029
- Cool Blue #4984B8 ΔE 0.033
- Water Blue #0E87CC ΔE 0.037
- Teal Blue #01889F ΔE 0.039
- Cerulean #457B9D ΔE 0.043
- Windows Blue #3778BF ΔE 0.044
Use #1584B4 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.