#2640A8
Closest named color: Sapphire (#2138AB). oklch(42.1% 0.17 267.5), rgb(38, 64, 168).
Aa
White text reads best on this color (8.81:1).
About this color
#2640A8 is a dark, vivid blue. In OKLCH its lightness is 42%, its chroma 0.170 and its hue 268°. Its hue sits on the cool side of the wheel. The nearest named color is Sapphire (#2138AB), ΔE 0.020 away. White text reads best on it, at 8.81:1.
| Hue family | Blues |
| Lightness | dark (42%) |
| Chroma | vivid (0.170) |
| Temperature | cool |
| Nearest name | Sapphire (#2138AB) |
| Black text | 2.38:1 |
| White text | 8.81:1 |
Values
| HEX | #2640A8 |
| RGB | rgb(38, 64, 168) |
| HSL | hsl(228, 63%, 40%) |
| OKLCH | oklch(42.1% 0.17 267.5) |
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 #2640A8 | 8.81:1 | AAA | Lc -94.1 | Preferred for body text |
| Black text on #2640A8 | 2.38:1 | Fails | Lc 14.4 | Not readable |
| #2640A8 text on white | 8.81:1 | AAA | Lc 89.6 | Fine for body text |
| #2640A8 text on black | 2.38:1 | Fails | Lc -12.7 | Not readable |
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 800.
-
Step 50
50
#F1F5FF
oklch(97% 0.014 268.5)
-
Step 100
100
#E1EAFE
oklch(93.6% 0.029 266.4)
-
Step 200
200
#C9D9FF
oklch(88.6% 0.055 267.2)
-
Step 300
300
#A6BFFF
oklch(80.9% 0.095 267.8)
-
Step 400
400
#779BFF
oklch(70.7% 0.152 267.5)
-
Step 500
500
#557EFF
oklch(63.2% 0.197 267.3)
-
Step 600
600
#3C61F2
oklch(55.6% 0.221 267.5)
-
Step 700
700
#304FD2
oklch(49.1% 0.204 267.6)
-
Step 800
800 (this color)
#2640A8
oklch(42.1% 0.17 267.5)
-
Step 900
900
#233986
oklch(37.6% 0.132 267.5)
-
Step 950
950
#15224F
oklch(27% 0.084 268.2)
#2640A8 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) | #0051AB | 0.043 |
| Deuteranopia (no green cones) | #0044A6 | 0.023 |
| Tritanopia (no blue cones) | #005B6E | 0.133 |
| Achromatopsia (no color) | #4A4A4A | 0.170 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2640A8
#2640A8
oklch(42.1% 0.17 267.5)
- #614A00
#614A00
oklch(42.2% 0.086 88.1)
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 #2640A8, closest first.
No curated palette has a color within ΔE 0.04 of #2640A8.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sapphire #2138AB ΔE 0.020
- Cobalt #1E488F ΔE 0.047
- Blue Blue #2242C7 ΔE 0.050
- Blueberry #464196 ΔE 0.051
- Majorelle Blue #3F37C9 ΔE 0.062
- Dark Slate Blue #483D8B ΔE 0.065
- Indigo Blue #3A18B1 ΔE 0.069
- Dusk Blue #26538D ΔE 0.070
Use #2640A8 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.