#17557B
Closest named color: Deep Sea Blue (#015482). oklch(43% 0.088 240.8), rgb(23, 85, 123).
Aa
White text reads best on this color (8.00:1).
About this color
#17557B is a dark, moderately saturated blue. In OKLCH its lightness is 43%, its chroma 0.088 and its hue 241°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sea Blue (#015482), ΔE 0.015 away. White text reads best on it, at 8.00:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.088) |
| Temperature | cool |
| Nearest name | Deep Sea Blue (#015482) |
| Black text | 2.62:1 |
| White text | 8.00:1 |
Values
| HEX | #17557B |
| RGB | rgb(23, 85, 123) |
| HSL | hsl(203, 68%, 29%) |
| OKLCH | oklch(43% 0.088 240.8) |
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 #17557B | 8.00:1 | AAA | Lc -92.1 | Preferred for body text |
| Black text on #17557B | 2.62:1 | Fails | Lc 16.6 | Dividers and decoration only |
| #17557B text on white | 8.00:1 | AAA | Lc 87.4 | Fine for body text |
| #17557B text on black | 2.62:1 | Fails | Lc -14.7 | 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
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E2EBF3
oklch(93.6% 0.015 244.7)
-
Step 200
200
#C9DCEB
oklch(88.5% 0.029 241.6)
-
Step 300
300
#A4C6DF
oklch(81% 0.051 240.1)
-
Step 400
400
#71A8CF
oklch(70.8% 0.081 240.3)
-
Step 500
500
#4891C3
oklch(63.1% 0.105 241.1)
-
Step 600
600
#247AAF
oklch(55.5% 0.114 241)
-
Step 700
700
#156797
oklch(49.1% 0.106 241)
-
Step 800
800 (this color)
#17557B
oklch(43% 0.088 240.8)
-
Step 900
900
#1A4662
oklch(37.8% 0.068 240)
-
Step 950
950
#11293A
oklch(27% 0.044 241.7)
#17557B 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) | #43567D | 0.044 |
| Deuteranopia (no green cones) | #354C7A | 0.035 |
| Tritanopia (no blue cones) | #005E62 | 0.058 |
| Achromatopsia (no color) | #505050 | 0.088 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #17557B
#17557B
oklch(43% 0.088 240.8)
- #724315
#724315
oklch(43% 0.087 60.6)
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 #17557B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sea Blue #015482 ΔE 0.015
- Light Navy #155084 ΔE 0.024
- Light Navy Blue #2E5A88 ΔE 0.033
- Dusk Blue #26538D ΔE 0.035
- YInMn Blue #415A77 ΔE 0.045
- Petrol #005F6A ΔE 0.049
- Denim Blue #3B5B92 ΔE 0.054
- Cobalt #1E488F ΔE 0.055
Use #17557B 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.