#333B9E
Closest named color: Sapphire (#2138AB). oklch(41% 0.159 273.6), rgb(51, 59, 158).
Aa
White text reads best on this color (9.29:1).
About this color
#333B9E is a dark, vivid blue. In OKLCH its lightness is 41%, its chroma 0.159 and its hue 274°. 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 9.29:1.
| Hue family | Blues |
| Lightness | dark (41%) |
| Chroma | vivid (0.159) |
| Temperature | cool |
| Nearest name | Sapphire (#2138AB) |
| Black text | 2.26:1 |
| White text | 9.29:1 |
Values
| HEX | #333B9E |
| RGB | rgb(51, 59, 158) |
| HSL | hsl(236, 51%, 41%) |
| OKLCH | oklch(41% 0.159 273.6) |
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 #333B9E | 9.29:1 | AAA | Lc -95.3 | Preferred for body text |
| Black text on #333B9E | 2.26:1 | Fails | Lc 13.0 | Not readable |
| #333B9E text on white | 9.29:1 | AAA | Lc 90.9 | Preferred for body text |
| #333B9E text on black | 2.26:1 | Fails | Lc -11.4 | 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
#F3F5FE
oklch(97.1% 0.012 276.1)
-
Step 100
100
#E4E9FC
oklch(93.6% 0.026 274.1)
-
Step 200
200
#CED8FC
oklch(88.6% 0.051 273.1)
-
Step 300
300
#ADBDFD
oklch(80.9% 0.092 273.3)
-
Step 400
400
#8498FC
oklch(70.8% 0.148 273.5)
-
Step 500
500
#687AFA
oklch(63.1% 0.19 273.7)
-
Step 600
600
#525FE9
oklch(55.6% 0.206 273.5)
-
Step 700
700
#434DCA
oklch(49% 0.191 273.5)
-
Step 800
800 (this color)
#333B9E
oklch(41% 0.159 273.6)
-
Step 900
900
#2F3882
oklch(37.8% 0.124 273.7)
-
Step 950
950
#1B214C
oklch(26.9% 0.079 273.9)
#333B9E 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) | #004CA1 | 0.050 |
| Deuteranopia (no green cones) | #00429C | 0.040 |
| Tritanopia (no blue cones) | #005467 | 0.129 |
| Achromatopsia (no color) | #474747 | 0.159 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #333B9E
#333B9E
oklch(41% 0.159 273.6)
- #5A4900
#5A4900
oklch(41.1% 0.084 93.6)
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 #333B9E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sapphire #2138AB ΔE 0.031
- Blueberry #464196 ΔE 0.036
- Dark Slate Blue #483D8B ΔE 0.046
- Cobalt #1E488F ΔE 0.046
- Indigo Blue #3A18B1 ΔE 0.064
- Blue Blue #2242C7 ΔE 0.069
- Majorelle Blue #3F37C9 ΔE 0.071
- Dusk Blue #26538D ΔE 0.072
Use #333B9E 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.