#557DBF
Closest named color: Cool Blue (#4984B8). oklch(59% 0.111 260), rgb(85, 125, 191).
Aa
Black text reads best on this color (5.07:1).
About this color
#557DBF is a medium-dark, moderately saturated blue. In OKLCH its lightness is 59%, its chroma 0.111 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.027 away. Black text reads best on it, at 5.07:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.111) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.07:1 |
| White text | 4.14:1 |
Values
| HEX | #557DBF |
| RGB | rgb(85, 125, 191) |
| HSL | hsl(217, 45%, 54%) |
| OKLCH | oklch(59% 0.111 260) |
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 #557DBF | 4.14:1 | AA large text | Lc -73.8 | Content text, not long reading |
| Black text on #557DBF | 5.07:1 | AA | Lc 35.7 | Non-text elements, placeholder text |
| #557DBF text on white | 4.14:1 | AA large text | Lc 68.3 | Content text, not long reading |
| #557DBF text on black | 5.07:1 | AA | Lc -33.3 | 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 600.
-
Step 50
50
#F3F6FA
oklch(97.2% 0.006 255.5)
-
Step 100
100
#E4EAF4
oklch(93.5% 0.015 260.7)
-
Step 200
200
#CFDAEC
oklch(88.5% 0.028 260.3)
-
Step 300
300
#AEC2E2
oklch(81% 0.05 259.8)
-
Step 400
400
#83A2D3
oklch(70.7% 0.08 259.4)
-
Step 500
500
#648AC7
oklch(63.1% 0.102 259.6)
-
Step 600
600 (this color)
#557DBF
oklch(59% 0.111 260)
-
Step 700
700
#3C609B
oklch(49.1% 0.104 259.8)
-
Step 800
800
#324F7E
oklch(42.8% 0.086 259.7)
-
Step 900
900
#2C4265
oklch(37.8% 0.066 259.4)
-
Step 950
950
#1A273B
oklch(27.1% 0.042 258.8)
#557DBF 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) | #6282C2 | 0.022 |
| Deuteranopia (no green cones) | #5578BE | 0.014 |
| Tritanopia (no blue cones) | #108C95 | 0.100 |
| Achromatopsia (no color) | #7D7D7D | 0.111 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #557DBF
#557DBF
oklch(59% 0.111 260)
- #A0751E
#A0751E
oklch(59.1% 0.112 80.1)
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 #557DBF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.027
- Steel Blue #4682B4 ΔE 0.029
- Windows Blue #3778BF ΔE 0.034
- Off Blue #5684AE ΔE 0.037
- Dusty Blue #5A86AD ΔE 0.043
- Water Blue #0E87CC ΔE 0.048
- Faded Blue #658CBB ΔE 0.050
- Flat Blue #3C73A8 ΔE 0.052
Use #557DBF 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.