#557DCF
Closest named color: Windows Blue (#3778BF). oklch(59.9% 0.133 263.3), rgb(85, 125, 207).
Aa
Black text reads best on this color (5.22:1).
About this color
#557DCF is a medium-dark, moderately saturated blue. In OKLCH its lightness is 60%, its chroma 0.133 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.042 away. Black text reads best on it, at 5.22:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | moderately saturated (0.133) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 5.22:1 |
| White text | 4.02:1 |
Values
| HEX | #557DCF |
| RGB | rgb(85, 125, 207) |
| HSL | hsl(220, 56%, 57%) |
| OKLCH | oklch(59.9% 0.133 263.3) |
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 #557DCF | 4.02:1 | AA large text | Lc -72.8 | Content text, not long reading |
| Black text on #557DCF | 5.22:1 | AA | Lc 36.8 | Non-text elements, placeholder text |
| #557DCF text on white | 4.02:1 | AA large text | Lc 67.3 | Content text, not long reading |
| #557DCF text on black | 5.22:1 | AA | Lc -34.4 | Non-text elements, placeholder text |
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 500.
-
Step 50
50
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E3EAF7
oklch(93.6% 0.019 263)
-
Step 200
200
#CDDAF2
oklch(88.6% 0.036 262.8)
-
Step 300
300
#ABC1EC
oklch(80.9% 0.066 263.7)
-
Step 400
400
#7EA0E2
oklch(70.7% 0.104 263.1)
-
Step 500
500 (this color)
#557DCF
oklch(59.9% 0.133 263.3)
-
Step 600
600
#456FC7
oklch(55.6% 0.145 263.3)
-
Step 700
700
#375CAC
oklch(49% 0.135 263.5)
-
Step 800
800
#2E4C8B
oklch(42.7% 0.111 263.3)
-
Step 900
900
#29406F
oklch(37.8% 0.086 263.2)
-
Step 950
950
#182641
oklch(27.1% 0.054 262.5)
#557DCF 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) | #5A85D2 | 0.023 |
| Deuteranopia (no green cones) | #4A7ACD | 0.015 |
| Tritanopia (no blue cones) | #008F9C | 0.116 |
| Achromatopsia (no color) | #7F7F7F | 0.133 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #557DCF
#557DCF
oklch(59.9% 0.133 263.3)
- #A37800
#A37800
oklch(59.9% 0.123 83.4)
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 #557DCF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.042
- Cool Blue #4984B8 ΔE 0.046
- Water Blue #0E87CC ΔE 0.049
- Dark Sky Blue #448EE4 ΔE 0.050
- Steel Blue #4682B4 ΔE 0.050
- Soft Blue #6488EA ΔE 0.051
- Off Blue #5684AE ΔE 0.059
- Faded Blue #658CBB ΔE 0.061
Use #557DCF 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.