#1F5999
Closest named color: Dusk Blue (#26538D). oklch(46.1% 0.12 253.7), rgb(31, 89, 153).
Aa
White text reads best on this color (7.12:1).
About this color
#1F5999 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 46%, its chroma 0.120 and its hue 254°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.024 away. White text reads best on it, at 7.12:1.
| Hue family | Blues |
| Lightness | medium-dark (46%) |
| Chroma | moderately saturated (0.120) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.94:1 |
| White text | 7.12:1 |
Values
| HEX | #1F5999 |
| RGB | rgb(31, 89, 153) |
| HSL | hsl(211, 66%, 36%) |
| OKLCH | oklch(46.1% 0.12 253.7) |
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 #1F5999 | 7.12:1 | AAA | Lc -89.3 | Fine for body text |
| Black text on #1F5999 | 2.94:1 | Fails | Lc 19.7 | Dividers and decoration only |
| #1F5999 text on white | 7.12:1 | AAA | Lc 84.3 | Fine for body text |
| #1F5999 text on black | 2.94:1 | Fails | Lc -17.6 | 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 700.
-
Step 50
50
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E2EBF5
oklch(93.6% 0.017 250.8)
-
Step 200
200
#CBDBEF
oklch(88.6% 0.033 254)
-
Step 300
300
#A7C3E6
oklch(80.8% 0.058 254.2)
-
Step 400
400
#77A4DA
oklch(70.8% 0.093 253.5)
-
Step 500
500
#538CCF
oklch(63.1% 0.118 253.6)
-
Step 600
600
#3675BC
oklch(55.6% 0.128 253.4)
-
Step 700
700 (this color)
#1F5999
oklch(46.1% 0.12 253.7)
-
Step 800
800
#235084
oklch(42.7% 0.1 253.9)
-
Step 900
900
#22436A
oklch(37.8% 0.078 253.9)
-
Step 950
950
#14273E
oklch(26.9% 0.05 254.1)
#1F5999 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) | #3A5E9C | 0.030 |
| Deuteranopia (no green cones) | #255398 | 0.017 |
| Tritanopia (no blue cones) | #006871 | 0.091 |
| Achromatopsia (no color) | #585858 | 0.120 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1F5999
#1F5999
oklch(46.1% 0.12 253.7)
- #784E00
#784E00
oklch(46% 0.098 73.6)
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 #1F5999, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.024
- Denim Blue #3B5B92 ΔE 0.029
- Light Navy Blue #2E5A88 ΔE 0.030
- Light Navy #155084 ΔE 0.042
- Peacock Blue #016795 ΔE 0.043
- Deep Sea Blue #015482 ΔE 0.043
- Dusky Blue #475F94 ΔE 0.047
- Denim #3B638C ΔE 0.049
Use #1F5999 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.