#257BA1
Closest named color: Cerulean (#457B9D). oklch(55% 0.098 232), rgb(37, 123, 161).
Aa
White text reads best on this color (4.74:1).
About this color
#257BA1 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.098 and its hue 232°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean (#457B9D), ΔE 0.024 away. White text reads best on it, at 4.74:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.098) |
| Temperature | cool |
| Nearest name | Cerulean (#457B9D) |
| Black text | 4.42:1 |
| White text | 4.74:1 |
Values
| HEX | #257BA1 |
| RGB | rgb(37, 123, 161) |
| HSL | hsl(198, 63%, 39%) |
| OKLCH | oklch(55% 0.098 232) |
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 #257BA1 | 4.74:1 | AA | Lc -78.0 | Fine for body text |
| Black text on #257BA1 | 4.42:1 | AA large text | Lc 31.5 | Non-text elements, placeholder text |
| #257BA1 text on white | 4.74:1 | AA | Lc 72.6 | Content text, not long reading |
| #257BA1 text on black | 4.42:1 | AA large text | Lc -29.1 | 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 600.
-
Step 50
50
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E2ECF1
oklch(93.7% 0.013 228.9)
-
Step 200
200
#CADCE7
oklch(88.4% 0.025 234.5)
-
Step 300
300
#A5C6D9
oklch(80.9% 0.044 233.3)
-
Step 400
400
#72A9C5
oklch(70.7% 0.071 231.2)
-
Step 500
500
#4A93B7
oklch(63.1% 0.091 232.1)
-
Step 600
600 (this color)
#257BA1
oklch(55% 0.098 232)
-
Step 700
700
#18698B
oklch(49.1% 0.091 231.7)
-
Step 800
800
#185671
oklch(42.8% 0.075 231.5)
-
Step 900
900
#1C475C
oklch(37.8% 0.059 232.6)
-
Step 950
950
#122A36
oklch(27.2% 0.037 232.2)
#257BA1 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) | #687AA3 | 0.065 |
| Deuteranopia (no green cones) | #576EA0 | 0.054 |
| Tritanopia (no blue cones) | #008588 | 0.058 |
| Achromatopsia (no color) | #737373 | 0.099 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #257BA1
#257BA1
oklch(55% 0.098 232)
- #9E6038
#9E6038
oklch(55% 0.098 52.2)
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 #257BA1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean #457B9D ΔE 0.024
- Nice Blue #107AB0 ΔE 0.025
- Ocean #017B92 ΔE 0.029
- Dull Blue #49759C ΔE 0.030
- Muted Blue #3B719F ΔE 0.030
- Sea Blue #047495 ΔE 0.030
- Flat Blue #3C73A8 ΔE 0.032
- Ocean Blue #03719C ΔE 0.034
Use #257BA1 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.