#128FDD
Closest named color: Dark Sky Blue (#448EE4). oklch(62.7% 0.152 244.7), rgb(18, 143, 221).
Aa
Black text reads best on this color (5.99:1).
About this color
#128FDD is a medium-light, vivid blue. In OKLCH its lightness is 63%, its chroma 0.152 and its hue 245°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.028 away. Black text reads best on it, at 5.99:1.
| Hue family | Blues |
| Lightness | medium-light (63%) |
| Chroma | vivid (0.152) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 5.99:1 |
| White text | 3.50:1 |
Values
| HEX | #128FDD |
| RGB | rgb(18, 143, 221) |
| HSL | hsl(203, 85%, 47%) |
| OKLCH | oklch(62.7% 0.152 244.7) |
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 #128FDD | 3.50:1 | AA large text | Lc -67.4 | Content text, not long reading |
| Black text on #128FDD | 5.99:1 | AA | Lc 42.1 | Non-text elements, placeholder text |
| #128FDD text on white | 3.50:1 | AA large text | Lc 62.0 | Content text, not long reading |
| #128FDD text on black | 5.99:1 | AA | Lc -39.7 | 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 500.
-
Step 50
50
#F0F6FC
oklch(97% 0.01 247.9)
-
Step 100
100
#DEECF8
oklch(93.6% 0.022 243.8)
-
Step 200
200
#C3DDF3
oklch(88.5% 0.041 243.7)
-
Step 300
300
#98C6EE
oklch(80.8% 0.075 245.2)
-
Step 400
400
#5AA8E6
oklch(70.8% 0.119 244.6)
-
Step 500
500 (this color)
#128FDD
oklch(62.7% 0.152 244.7)
-
Step 600
600
#0079BE
oklch(55.6% 0.139 244.6)
-
Step 700
700
#0066A1
oklch(49.2% 0.123 244.5)
-
Step 800
800
#005385
oklch(42.7% 0.107 244.8)
-
Step 900
900
#004570
oklch(37.7% 0.095 244.9)
-
Step 950
950
#042943
oklch(27.1% 0.063 244.6)
#128FDD 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) | #6992E0 | 0.062 |
| Deuteranopia (no green cones) | #4D81DC | 0.045 |
| Tritanopia (no blue cones) | #00A2AB | 0.106 |
| Achromatopsia (no color) | #898989 | 0.152 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #128FDD
#128FDD
oklch(62.7% 0.152 244.7)
- #C17300
#C17300
oklch(62.7% 0.141 64.9)
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 #128FDD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.028
- Water Blue #0E87CC ΔE 0.032
- Chefchaouen Blue #4895EF ΔE 0.044
- Dodger Blue #1E90FF ΔE 0.052
- Cool Blue #4984B8 ΔE 0.060
- Soft Blue #6488EA ΔE 0.062
- Cornflower Blue #6495ED ΔE 0.064
- Blue NCS #118AB2 ΔE 0.066
Use #128FDD 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.