#2F51A5
Closest named color: Dusk Blue (#26538D). oklch(45.8% 0.141 264.8), rgb(47, 81, 165).
Aa
White text reads best on this color (7.39:1).
About this color
#2F51A5 is a medium-dark, vivid blue. In OKLCH its lightness is 46%, its chroma 0.141 and its hue 265°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.042 away. White text reads best on it, at 7.39:1.
| Hue family | Blues |
| Lightness | medium-dark (46%) |
| Chroma | vivid (0.141) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.84:1 |
| White text | 7.39:1 |
Values
| HEX | #2F51A5 |
| RGB | rgb(47, 81, 165) |
| HSL | hsl(223, 56%, 42%) |
| OKLCH | oklch(45.8% 0.141 264.8) |
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 #2F51A5 | 7.39:1 | AAA | Lc -90.2 | Preferred for body text |
| Black text on #2F51A5 | 2.84:1 | Fails | Lc 18.7 | Dividers and decoration only |
| #2F51A5 text on white | 7.39:1 | AAA | Lc 85.3 | Fine for body text |
| #2F51A5 text on black | 2.84:1 | Fails | Lc -16.7 | Dividers and decoration only |
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
#F2F6FD
oklch(97.2% 0.01 261.8)
-
Step 100
100
#E2EAFA
oklch(93.6% 0.023 264.5)
-
Step 200
200
#CAD9F8
oklch(88.4% 0.046 264.9)
-
Step 300
300
#A6C0F7
oklch(80.8% 0.083 264.9)
-
Step 400
400
#779EF3
oklch(70.7% 0.132 264.6)
-
Step 500
500
#5683EE
oklch(63.1% 0.168 264.8)
-
Step 600
600
#3C6ADD
oklch(55.7% 0.183 264.7)
-
Step 700
700
#2F57C0
oklch(49.1% 0.171 264.9)
-
Step 800
800 (this color)
#2F51A5
oklch(45.8% 0.141 264.8)
-
Step 900
900
#243D7B
oklch(37.6% 0.11 265)
-
Step 950
950
#152448
oklch(26.9% 0.07 265)
#2F51A5 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) | #1F5BA8 | 0.027 |
| Deuteranopia (no green cones) | #0050A3 | 0.029 |
| Tritanopia (no blue cones) | #006573 | 0.114 |
| Achromatopsia (no color) | #565656 | 0.141 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2F51A5
#2F51A5
oklch(45.8% 0.141 264.8)
- #6F5200
#6F5200
oklch(45.7% 0.094 84.9)
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 #2F51A5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.042
- Cobalt #1E488F ΔE 0.047
- Denim Blue #3B5B92 ΔE 0.048
- Blueberry #464196 ΔE 0.050
- Twilight #4E518B ΔE 0.056
- Light Navy Blue #2E5A88 ΔE 0.058
- Light Navy #155084 ΔE 0.060
- Dusky Blue #475F94 ΔE 0.061
Use #2F51A5 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.