#289BE5
Closest named color: Chefchaouen Blue (#4895EF). oklch(66.3% 0.147 243.1), rgb(40, 155, 229).
Aa
Black text reads best on this color (6.91:1).
About this color
#289BE5 is a medium-light, vivid blue. In OKLCH its lightness is 66%, its chroma 0.147 and its hue 243°. Its hue sits on the cool side of the wheel. The nearest named color is Chefchaouen Blue (#4895EF), ΔE 0.030 away. Black text reads best on it, at 6.91:1.
| Hue family | Blues |
| Lightness | medium-light (66%) |
| Chroma | vivid (0.147) |
| Temperature | cool |
| Nearest name | Chefchaouen Blue (#4895EF) |
| Black text | 6.91:1 |
| White text | 3.03:1 |
Values
| HEX | #289BE5 |
| RGB | rgb(40, 155, 229) |
| HSL | hsl(203, 78%, 53%) |
| OKLCH | oklch(66.3% 0.147 243.1) |
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 #289BE5 | 3.03:1 | AA large text | Lc -62.1 | Content text, not long reading |
| Black text on #289BE5 | 6.91:1 | AA | Lc 47.3 | Large or bold text, headings |
| #289BE5 text on white | 3.03:1 | AA large text | Lc 56.7 | Large or bold text, headings |
| #289BE5 text on black | 6.91:1 | AA | Lc -45.1 | Large or bold text, headings |
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
#DFECF7
oklch(93.7% 0.02 243.4)
-
Step 200
200
#C3DDF2
oklch(88.5% 0.04 242.4)
-
Step 300
300
#99C7EC
oklch(81% 0.072 243)
-
Step 400
400
#5BA8E2
oklch(70.6% 0.115 243.2)
-
Step 500
500 (this color)
#289BE5
oklch(66.3% 0.147 243.1)
-
Step 600
600
#007ABB
oklch(55.7% 0.134 242.9)
-
Step 700
700
#00669E
oklch(49% 0.119 243.2)
-
Step 800
800
#005483
oklch(42.8% 0.104 243)
-
Step 900
900
#00466E
oklch(37.8% 0.091 242.8)
-
Step 950
950
#042941
oklch(27% 0.06 242.6)
#289BE5 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) | #789DE8 | 0.066 |
| Deuteranopia (no green cones) | #5E8CE4 | 0.051 |
| Tritanopia (no blue cones) | #00ADB5 | 0.101 |
| Achromatopsia (no color) | #949494 | 0.147 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #289BE5
#289BE5
oklch(66.3% 0.147 243.1)
- #D17C11
#D17C11
oklch(66.4% 0.147 63.2)
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 #289BE5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chefchaouen Blue #4895EF ΔE 0.030
- Dark Sky Blue #448EE4 ΔE 0.036
- Cornflower Blue #6495ED ΔE 0.048
- Dodger Blue #1E90FF ΔE 0.053
- Soft Blue #6488EA ΔE 0.064
- Water Blue #0E87CC ΔE 0.064
- Faded Blue #658CBB ΔE 0.074
- Cool Blue #4984B8 ΔE 0.081
Use #289BE5 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.