#666666
#666666 is rgb(102, 102, 102), or hsl(0, 0%, 40%). The nearest reference Tailwind v4 token is zinc-500 (#71717b), not an exact match.
Conversions
WCAG contrast
| Background | Ratio | AA text | AA large | AAA text |
|---|---|---|---|---|
| white | 5.74:1 | pass | pass | fail |
| black | 3.66:1 | fail | pass | fail |
| slate-900 | 3.11:1 | fail | pass | fail |
| gray-100 | 5.22:1 | pass | pass | fail |
Ratios use WCAG relative luminance for opaque sRGB colors. Normal text requires 4.5:1, or 7:1 at AAA. Large text requires 3:1: at least 24 CSS pixels, or about 18.67 CSS pixels when bold. Pass/fail uses the unrounded ratio. Contrast alone is not a full accessibility assessment.
Colors paired with #666666 in real UI palettes
These colors appear alongside #666666 in StyleKit's curated palettes. Co-occurrence is not a promise of text readability; each pair includes its measured contrast.
- #111111
Used together in Monochrome.
3.29:1
Not for normal text - #999999
Used together in Monochrome.
2.02:1
Not for normal text - #cccccc
Used together in Monochrome.
3.58:1
Not for normal text - #fafafa
Used together in Monochrome.
5.50:1
AA normal text
A readable starting point
white text on #666666: 5.74:1 contrast.
Design styles using this color
Tints and shades
Lightness ladder in HSL space, from the lightest tint to the darkest shade of #666666.
Similar colors in the library
Nearest swatches by perceptual OKLab distance across all curated style palettes.
AI prompt snippet
Use #666666 as the accent color, following the Monochrome style: rgb(102, 102, 102), nearest Tailwind token zinc-500. Keep text contrast at least 4.5:1 (this color scores 5.74:1 on white, 3.66:1 on black).
Paste this into ChatGPT, Claude, Cursor, or v0 to use #666666 with correct contrast constraints. Browse all palette colors.
Questions about #666666
What color is #666666?
#666666 is rgb(102, 102, 102), or hsl(0, 0%, 40%). The nearest reference Tailwind v4 token is zinc-500 (#71717b), not an exact match.
What text color should I use on #666666?
White (#ffffff) has the higher black-or-white contrast against #666666: 5.74:1. This calculation assumes opaque, flat sRGB colors. Normal text requires 4.5:1 and large text 3:1 under WCAG 2.2 SC 1.4.3; it is not a complete accessibility assessment.
How can I use exactly #666666 in Tailwind CSS?
Use bg-[#666666], text-[#666666], or a CSS custom property instead of substituting a nearby named token. The reference palette is Tailwind CSS 4.1.18, converted from OKLCH to sRGB hex; newer Tailwind versions and custom themes can differ.
Sources and calculation limits
Reference palette: Tailwind CSS 4.1.18, converted from OKLCH to sRGB hex. Named tokens are versioned approximations; use the exact hex utilities when matching an existing design. Palette pairings come from the linked StyleKit definitions, not external popularity or preference data.