#343FA5
Closest named color: Sapphire (#2138AB). oklch(42.4% 0.163 272.6), rgb(52, 63, 165).
Aa
White text reads best on this color (8.74:1).
About this color
#343FA5 is a dark, vivid blue. In OKLCH its lightness is 42%, its chroma 0.163 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Sapphire (#2138AB), ΔE 0.031 away. White text reads best on it, at 8.74:1.
| Hue family | Blues |
| Lightness | dark (42%) |
| Chroma | vivid (0.163) |
| Temperature | cool |
| Nearest name | Sapphire (#2138AB) |
| Black text | 2.40:1 |
| White text | 8.74:1 |
Values
| HEX | #343FA5 |
| RGB | rgb(52, 63, 165) |
| HSL | hsl(234, 52%, 43%) |
| OKLCH | oklch(42.4% 0.163 272.6) |
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 #343FA5 | 8.74:1 | AAA | Lc -94.0 | Preferred for body text |
| Black text on #343FA5 | 2.40:1 | Fails | Lc 14.5 | Not readable |
| #343FA5 text on white | 8.74:1 | AAA | Lc 89.5 | Fine for body text |
| #343FA5 text on black | 2.40:1 | Fails | Lc -12.8 | 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
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E3E9FD
oklch(93.5% 0.028 272.5)
-
Step 200
200
#CDD8FD
oklch(88.6% 0.052 272.2)
-
Step 300
300
#ACBDFF
oklch(80.9% 0.095 273)
-
Step 400
400
#8198FF
oklch(70.7% 0.153 272.5)
-
Step 500
500
#657AFD
oklch(63.1% 0.195 272.7)
-
Step 600
600
#4F5FEC
oklch(55.7% 0.211 272.6)
-
Step 700
700
#404DCD
oklch(49.1% 0.196 272.4)
-
Step 800
800 (this color)
#343FA5
oklch(42.4% 0.163 272.6)
-
Step 900
900
#2D3884
oklch(37.8% 0.127 272.6)
-
Step 950
950
#1A214D
oklch(26.9% 0.081 272.9)
#343FA5 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) | #0050A8 | 0.049 |
| Deuteranopia (no green cones) | #0046A3 | 0.039 |
| Tritanopia (no blue cones) | #00596C | 0.133 |
| Achromatopsia (no color) | #4B4B4B | 0.163 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #343FA5
#343FA5
oklch(42.4% 0.163 272.6)
- #5F4C00
#5F4C00
oklch(42.4% 0.087 92.3)
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 #343FA5, closest first.
No curated palette has a color within ΔE 0.04 of #343FA5.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sapphire #2138AB ΔE 0.031
- Blueberry #464196 ΔE 0.037
- Cobalt #1E488F ΔE 0.048
- Dark Slate Blue #483D8B ΔE 0.051
- Blue Blue #2242C7 ΔE 0.057
- Majorelle Blue #3F37C9 ΔE 0.060
- Indigo Blue #3A18B1 ΔE 0.068
- Dusk Blue #26538D ΔE 0.069
Use #343FA5 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.