#1F577A
Closest named color: Deep Sea Blue (#015482). oklch(43.7% 0.082 240), rgb(31, 87, 122).
Aa
White text reads best on this color (7.77:1).
About this color
#1F577A is a dark, moderately saturated blue. In OKLCH its lightness is 44%, its chroma 0.082 and its hue 240°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sea Blue (#015482), ΔE 0.023 away. White text reads best on it, at 7.77:1.
| Hue family | Blues |
| Lightness | dark (44%) |
| Chroma | moderately saturated (0.082) |
| Temperature | cool |
| Nearest name | Deep Sea Blue (#015482) |
| Black text | 2.70:1 |
| White text | 7.77:1 |
Values
| HEX | #1F577A |
| RGB | rgb(31, 87, 122) |
| HSL | hsl(203, 59%, 30%) |
| OKLCH | oklch(43.7% 0.082 240) |
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 #1F577A | 7.77:1 | AAA | Lc -91.5 | Preferred for body text |
| Black text on #1F577A | 2.70:1 | Fails | Lc 17.3 | Dividers and decoration only |
| #1F577A text on white | 7.77:1 | AAA | Lc 86.7 | Fine for body text |
| #1F577A text on black | 2.70:1 | Fails | Lc -15.4 | 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
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E2EBF2
oklch(93.5% 0.014 241)
-
Step 200
200
#CADCE9
oklch(88.5% 0.026 239.1)
-
Step 300
300
#A6C5DD
oklch(80.9% 0.048 241.5)
-
Step 400
400
#74A7CC
oklch(70.6% 0.077 240.7)
-
Step 500
500
#4D91BF
oklch(63.1% 0.098 240.3)
-
Step 600
600
#2C7BAB
oklch(55.7% 0.106 239.7)
-
Step 700
700
#1E6793
oklch(49.1% 0.099 240.3)
-
Step 800
800 (this color)
#1F577A
oklch(43.7% 0.082 240)
-
Step 900
900
#1E4660
oklch(37.8% 0.063 239.9)
-
Step 950
950
#122938
oklch(27% 0.04 239.2)
#1F577A 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) | #47577C | 0.043 |
| Deuteranopia (no green cones) | #3A4E79 | 0.035 |
| Tritanopia (no blue cones) | #006063 | 0.056 |
| Achromatopsia (no color) | #525252 | 0.082 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1F577A
#1F577A
oklch(43.7% 0.082 240)
- #72461E
#72461E
oklch(43.7% 0.081 60.2)
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 #1F577A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sea Blue #015482 ΔE 0.023
- Light Navy Blue #2E5A88 ΔE 0.028
- Light Navy #155084 ΔE 0.031
- YInMn Blue #415A77 ΔE 0.037
- Dusk Blue #26538D ΔE 0.037
- Petrol #005F6A ΔE 0.044
- Denim Blue #3B5B92 ΔE 0.051
- Denim #3B638C ΔE 0.054
Use #1F577A 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.