#6599EF
Closest named color: Cornflower Blue (#6495ED). oklch(68.5% 0.139 260), rgb(101, 153, 239).
Aa
Black text reads best on this color (7.35:1).
About this color
#6599EF is a medium-light, moderately saturated blue. In OKLCH its lightness is 68%, its chroma 0.139 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Cornflower Blue (#6495ED), ΔE 0.011 away. Black text reads best on it, at 7.35:1.
| Hue family | Blues |
| Lightness | medium-light (68%) |
| Chroma | moderately saturated (0.139) |
| Temperature | cool |
| Nearest name | Cornflower Blue (#6495ED) |
| Black text | 7.35:1 |
| White text | 2.85:1 |
Values
| HEX | #6599EF |
| RGB | rgb(101, 153, 239) |
| HSL | hsl(217, 81%, 67%) |
| OKLCH | oklch(68.5% 0.139 260) |
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 #6599EF | 2.85:1 | Fails | Lc -59.8 | Large or bold text, headings |
| Black text on #6599EF | 7.35:1 | AAA | Lc 49.6 | Large or bold text, headings |
| #6599EF text on white | 2.85:1 | Fails | Lc 54.5 | Large or bold text, headings |
| #6599EF text on black | 7.35:1 | AAA | Lc -47.3 | 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 400.
-
Step 50
50
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E0EBFB
oklch(93.7% 0.025 257.6)
-
Step 200
200
#C7DAFA
oklch(88.4% 0.049 260.9)
-
Step 300
300
#A0C2F9
oklch(80.9% 0.087 259.9)
-
Step 400
400 (this color)
#6599EF
oklch(68.5% 0.139 260)
-
Step 500
500
#4385F3
oklch(63% 0.178 260)
-
Step 600
600
#236CE2
oklch(55.6% 0.194 260)
-
Step 700
700
#1559C4
oklch(49% 0.18 259.9)
-
Step 800
800
#154A9F
oklch(42.8% 0.149 259.9)
-
Step 900
900
#183F7E
oklch(37.8% 0.116 259.7)
-
Step 950
950
#0F254A
oklch(27% 0.074 260.2)
#6599EF 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) | #75A0F3 | 0.027 |
| Deuteranopia (no green cones) | #6393ED | 0.016 |
| Tritanopia (no blue cones) | #00ACB9 | 0.121 |
| Achromatopsia (no color) | #999999 | 0.139 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #6599EF
#6599EF
oklch(68.5% 0.139 260)
- #C68E0D
#C68E0D
oklch(68.4% 0.139 79.9)
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 #6599EF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cornflower Blue #6495ED ΔE 0.011
- Chefchaouen Blue #4895EF ΔE 0.030
- Soft Blue #6488EA ΔE 0.044
- Dark Sky Blue #448EE4 ΔE 0.048
- Periwinkle Blue #8F99FB ΔE 0.054
- Perrywinkle #8F8CE7 ΔE 0.057
- Lavender Blue #8B88F8 ΔE 0.063
- Dodger Blue #1E90FF ΔE 0.063
Use #6599EF 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.