#237FD5
Closest named color: Water Blue (#0E87CC). oklch(58.9% 0.155 251.4), rgb(35, 127, 213).
Aa
Black text reads best on this color (5.06:1).
About this color
#237FD5 is a medium-dark, vivid blue. In OKLCH its lightness is 59%, its chroma 0.155 and its hue 251°. Its hue sits on the cool side of the wheel. The nearest named color is Water Blue (#0E87CC), ΔE 0.029 away. Black text reads best on it, at 5.06:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | vivid (0.155) |
| Temperature | cool |
| Nearest name | Water Blue (#0E87CC) |
| Black text | 5.06:1 |
| White text | 4.14:1 |
Values
| HEX | #237FD5 |
| RGB | rgb(35, 127, 213) |
| HSL | hsl(209, 72%, 49%) |
| OKLCH | oklch(58.9% 0.155 251.4) |
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 #237FD5 | 4.14:1 | AA large text | Lc -73.5 | Content text, not long reading |
| Black text on #237FD5 | 5.06:1 | AA | Lc 36.1 | Non-text elements, placeholder text |
| #237FD5 text on white | 4.14:1 | AA large text | Lc 68.0 | Content text, not long reading |
| #237FD5 text on black | 5.06:1 | AA | Lc -33.6 | 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
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E0EBF7
oklch(93.5% 0.02 250.4)
-
Step 200
200
#C7DCF3
oklch(88.6% 0.039 250.7)
-
Step 300
300
#A0C4ED
oklch(80.8% 0.07 252)
-
Step 400
400
#6AA5E4
oklch(70.7% 0.112 251.1)
-
Step 500
500
#3E8DDC
oklch(63.2% 0.142 251.1)
-
Step 600
600 (this color)
#237FD5
oklch(58.9% 0.155 251.4)
-
Step 700
700
#0062AF
oklch(49.2% 0.144 251.3)
-
Step 800
800
#0A508D
oklch(42.6% 0.119 251.3)
-
Step 900
900
#144371
oklch(37.7% 0.093 251.4)
-
Step 950
950
#0E2842
oklch(27.1% 0.058 250.8)
#237FD5 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) | #5485D8 | 0.044 |
| Deuteranopia (no green cones) | #3675D3 | 0.027 |
| Tritanopia (no blue cones) | #00949F | 0.116 |
| Achromatopsia (no color) | #7D7D7D | 0.155 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #237FD5
#237FD5
oklch(58.9% 0.155 251.4)
- #AB6E00
#AB6E00
oklch(58.9% 0.127 71.3)
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 #237FD5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Water Blue #0E87CC ΔE 0.029
- Windows Blue #3778BF ΔE 0.036
- Dark Sky Blue #448EE4 ΔE 0.053
- Cool Blue #4984B8 ΔE 0.056
- Steel Blue #4682B4 ΔE 0.057
- Nice Blue #107AB0 ΔE 0.059
- Royal Blue #4169E1 ΔE 0.062
- Cerulean Blue #056EEE ΔE 0.063
Use #237FD5 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.