#003FB9
Closest named color: Sapphire (#2138AB). oklch(42.6% 0.2 262.2), rgb(0, 63, 185).
Aa
White text reads best on this color (8.70:1).
About this color
#003FB9 is a dark, vivid blue. In OKLCH its lightness is 43%, its chroma 0.200 and its hue 262°. 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 8.70:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | vivid (0.200) |
| Temperature | cool |
| Nearest name | Sapphire (#2138AB) |
| Black text | 2.41:1 |
| White text | 8.70:1 |
Values
| HEX | #003FB9 |
| RGB | rgb(0, 63, 185) |
| HSL | hsl(220, 100%, 36%) |
| OKLCH | oklch(42.6% 0.2 262.2) |
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 #003FB9 | 8.70:1 | AAA | Lc -93.3 | Preferred for body text |
| Black text on #003FB9 | 2.41:1 | Fails | Lc 15.3 | Dividers and decoration only |
| #003FB9 text on white | 8.70:1 | AAA | Lc 88.7 | Fine for body text |
| #003FB9 text on black | 2.41:1 | Fails | Lc -13.5 | 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
#F0F6FF
oklch(97.1% 0.014 258.3)
-
Step 100
100
#DFEAFF
oklch(93.5% 0.031 263.5)
-
Step 200
200
#C5DAFF
oklch(88.5% 0.056 261.8)
-
Step 300
300
#9FC1FF
oklch(80.9% 0.096 262.2)
-
Step 400
400
#6B9EFF
oklch(70.7% 0.153 262.2)
-
Step 500
500
#4282FF
oklch(63.2% 0.198 262)
-
Step 600
600
#1061FF
oklch(55.6% 0.245 262.2)
-
Step 700
700
#004EE0
oklch(49.1% 0.231 262.2)
-
Step 800
800 (this color)
#003FB9
oklch(42.6% 0.2 262.2)
-
Step 900
900
#0C3892
oklch(37.6% 0.156 262.3)
-
Step 950
950
#092256
oklch(27% 0.099 262.5)
#003FB9 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) | #0053BD | 0.049 |
| Deuteranopia (no green cones) | #0043B7 | 0.009 |
| Tritanopia (no blue cones) | #006076 | 0.151 |
| Achromatopsia (no color) | #4B4B4B | 0.200 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #003FB9
#003FB9
oklch(42.6% 0.2 262.2)
- #664900
#664900
oklch(42.6% 0.088 82.4)
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 #003FB9, closest first.
No curated palette has a color within ΔE 0.04 of #003FB9.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sapphire #2138AB ΔE 0.031
- Blue Blue #2242C7 ΔE 0.032
- Majorelle Blue #3F37C9 ΔE 0.058
- True Blue #010FCC ΔE 0.071
- Cobalt #1E488F ΔE 0.074
- Indigo Blue #3A18B1 ΔE 0.075
- Ultramarine Blue #1805DB ΔE 0.078
- Medium Blue #0000CD ΔE 0.079
Use #003FB9 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.