#257DA3
Closest named color: Cerulean (#457B9D). oklch(55.6% 0.099 231.5), rgb(37, 125, 163).
Aa
White text reads best on this color (4.62:1).
About this color
#257DA3 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 56%, its chroma 0.099 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 4.62:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.099) |
| Temperature | cool |
| Nearest name | Cerulean (#457B9D) |
| Black text | 4.54:1 |
| White text | 4.62:1 |
Values
| HEX | #257DA3 |
| RGB | rgb(37, 125, 163) |
| HSL | hsl(198, 63%, 39%) |
| OKLCH | oklch(55.6% 0.099 231.5) |
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 #257DA3 | 4.62:1 | AA | Lc -77.2 | Fine for body text |
| Black text on #257DA3 | 4.54:1 | AA | Lc 32.3 | Non-text elements, placeholder text |
| #257DA3 text on white | 4.62:1 | AA | Lc 71.8 | Content text, not long reading |
| #257DA3 text on black | 4.54:1 | AA | Lc -29.9 | 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
#A4C6D9
oklch(80.8% 0.045 232.5)
-
Step 400
400
#72A9C6
oklch(70.7% 0.072 232.1)
-
Step 500
500
#4993B7
oklch(63.1% 0.091 231.8)
-
Step 600
600 (this color)
#257DA3
oklch(55.6% 0.099 231.5)
-
Step 700
700
#15698C
oklch(49% 0.093 232)
-
Step 800
800
#165671
oklch(42.7% 0.076 231)
-
Step 900
900
#1B475C
oklch(37.7% 0.06 232.2)
-
Step 950
950
#112A36
oklch(27.1% 0.038 231.3)
#257DA3 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) | #6A7BA5 | 0.066 |
| Deuteranopia (no green cones) | #596FA2 | 0.057 |
| Tritanopia (no blue cones) | #00878A | 0.058 |
| Achromatopsia (no color) | #757575 | 0.100 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #257DA3
#257DA3
oklch(55.6% 0.099 231.5)
- #A16139
#A16139
oklch(55.6% 0.1 51.4)
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 #257DA3, 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 0.026
- Ocean #017B92 ΔE 0.031
- Dull Blue #49759C ΔE 0.032
- Flat Blue #3C73A8 ΔE 0.034
- Stormy Blue #507B9C ΔE 0.035
- Muted Blue #3B719F ΔE 0.035
- Teal Blue #01889F ΔE 0.035
Use #257DA3 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.