#557FB0
Closest named color: Off Blue (#5684AE). oklch(58.7% 0.089 253), rgb(85, 127, 176).
Aa
Black text reads best on this color (5.04:1).
About this color
#557FB0 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 59%, its chroma 0.089 and its hue 253°. Its hue sits on the cool side of the wheel. The nearest named color is Off Blue (#5684AE), ΔE 0.016 away. Black text reads best on it, at 5.04:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.089) |
| Temperature | cool |
| Nearest name | Off Blue (#5684AE) |
| Black text | 5.04:1 |
| White text | 4.15:1 |
Values
| HEX | #557FB0 |
| RGB | rgb(85, 127, 176) |
| HSL | hsl(212, 37%, 51%) |
| OKLCH | oklch(58.7% 0.089 253) |
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 #557FB0 | 4.15:1 | AA large text | Lc -74.0 | Content text, not long reading |
| Black text on #557FB0 | 5.04:1 | AA | Lc 35.6 | Non-text elements, placeholder text |
| #557FB0 text on white | 4.15:1 | AA large text | Lc 68.5 | Content text, not long reading |
| #557FB0 text on black | 5.04:1 | AA | Lc -33.1 | 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
#F3F6F9
oklch(97.2% 0.005 247.9)
-
Step 100
100
#E5EAF2
oklch(93.6% 0.012 259.8)
-
Step 200
200
#CFDAE8
oklch(88.4% 0.023 254.4)
-
Step 300
300
#AFC3DB
oklch(81% 0.04 253.1)
-
Step 400
400
#85A3C8
oklch(70.6% 0.064 253.9)
-
Step 500
500
#658CBA
oklch(63% 0.082 253.1)
-
Step 600
600 (this color)
#557FB0
oklch(58.7% 0.089 253)
-
Step 700
700
#3D638F
oklch(49.1% 0.083 253)
-
Step 800
800
#335174
oklch(42.8% 0.069 253.1)
-
Step 900
900
#2D435D
oklch(37.7% 0.053 253.2)
-
Step 950
950
#1A2737
oklch(26.9% 0.035 254.1)
#557FB0 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) | #6B81B2 | 0.028 |
| Deuteranopia (no green cones) | #6078AF | 0.022 |
| Tritanopia (no blue cones) | #278A90 | 0.078 |
| Achromatopsia (no color) | #7C7C7C | 0.089 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #557FB0
#557FB0
oklch(58.7% 0.089 253)
- #9C743C
#9C743C
oklch(58.7% 0.089 73.8)
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 #557FB0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Off Blue #5684AE ΔE 0.016
- Steel Blue #4682B4 ΔE 0.016
- Cool Blue #4984B8 ΔE 0.018
- Dusty Blue #5A86AD ΔE 0.023
- Stormy Blue #507B9C ΔE 0.032
- Cerulean #457B9D ΔE 0.036
- Dull Blue #49759C ΔE 0.042
- Faded Blue #658CBB ΔE 0.044
Use #557FB0 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.