# #51666c

A color — cool, muted. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#51666c`
- RGB: rgb(81, 102, 108)
- HSL: hsl(193, 14%, 37%)
- OKLCH: oklch(0.495 0.027 217)
- Relative luminance: 0.1233
- Nearest named color: Dark Forest (#556962, Δ 2.158) — https://brandsweets.com/colors/dark-forest
- Moods: cool, muted
- Page: https://brandsweets.com/colors/51666c

## Tints & shades

- Tints (toward white): #5e767d, #6b878e, #7c959c, #8ea3a9, #a2b4b9, #b3c2c6, #c5d0d3, #d6dee0, #e8eced, #f9fafb
- Shades (toward black): #4b5e63, #425357, #3b4a4e, #354246, #2e3a3d, #252f31, #1f2729, #181e20, #0f1314, #090b0c

## Harmonies

- Complementary: #6c5751
- Analogous: #516c64, #51596c
- Triadic: #6c5166, #666c51
- Split-complementary: #6c5159, #6c6451
- Tetradic: #64516c, #6c5751, #596c51

## Colors that go with #51666c

Named partners (harmony on the OKLCH wheel, co-occurrence in curated palettes and brand systems, and the neutrals that carry it), best first:

- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black that reads cleanly against #51666c without the hard edge of pure #000. Seen in: Gusto (https://brandsweets.com/colors/brands/gusto-com), Harbour (https://brandsweets.com/palettes/cool#harbour), Pampers (https://brandsweets.com/colors/brands/pampers-com), Campus (https://brandsweets.com/palettes/friendly#campus). — https://brandsweets.com/colors/charcoal
- **Champagne** #f7e7ce [pool] — 5 real palettes, including Darkroom and BrandSweets's brand system put Champagne beside #51666c, as the surface under it. Seen in: Darkroom (https://brandsweets.com/palettes/muted#darkroom), BrandSweets (https://brandsweets.com/colors/brands/brandsweets), Forest Floor (https://brandsweets.com/palettes/dark#forest-floor), Coffee Bar (https://brandsweets.com/palettes/dark#coffee-bar). — https://brandsweets.com/colors/champagne
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #51666c: 4 real palettes, including Ink & Paper and Fintech Trust, as the accent. Seen in: Ink & Paper (https://brandsweets.com/palettes/minimal#ink-and-paper), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Intel (https://brandsweets.com/colors/brands/intel-com), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/cobalt
- **Copper** #b87333 [pool] — Designers have shipped Copper with #51666c: 5 real palettes, including Desert Road and Dusk, as the lead colour. Seen in: Desert Road (https://brandsweets.com/palettes/warm#desert-road), Dusk (https://brandsweets.com/palettes/cool#dusk), Clay & Linen (https://brandsweets.com/palettes/warm#clay-and-linen), Riverbed (https://brandsweets.com/palettes/muted#riverbed). — https://brandsweets.com/colors/copper
- **Crimson** #dc143c [pool] — Crimson is paired with #51666c in 8 real palettes, including Gemstone and Retro Pop, as the accent. Seen in: Gemstone (https://brandsweets.com/palettes/vivid#gemstone), Retro Pop (https://brandsweets.com/palettes/playful#retro-pop), Redfin (https://brandsweets.com/colors/brands/redfin-com), Wendy's (https://brandsweets.com/colors/brands/wendys-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #51666c: 10 real palettes, including HP's brand system and The New York Times's brand system, as the accent. Seen in: HP (https://brandsweets.com/colors/brands/hp-com), The New York Times (https://brandsweets.com/colors/brands/nytimes-com), Campus (https://brandsweets.com/palettes/friendly#campus), Dutch Bros (https://brandsweets.com/colors/brands/dutchbros-com). — https://brandsweets.com/colors/denim
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #51666c: 5 real palettes, including Fireside and Newsprint, as the lead colour. Seen in: Fireside (https://brandsweets.com/palettes/dark#fireside), Newsprint (https://brandsweets.com/palettes/editorial#newsprint), Wendy's (https://brandsweets.com/colors/brands/wendys-com), AT&T (https://brandsweets.com/colors/brands/att-com). — https://brandsweets.com/colors/firebrick
- **Goldenrod** #daa520 [pool] — Goldenrod shows up next to #51666c in 5 real palettes, including Mid-Century and Open House, as the accent. Seen in: Mid-Century (https://brandsweets.com/palettes/warm#mid-century), Open House (https://brandsweets.com/palettes/clean#open-house), Fireside (https://brandsweets.com/palettes/dark#fireside), Sapphire & Gold (https://brandsweets.com/palettes/luxury#sapphire-and-gold). — https://brandsweets.com/colors/goldenrod

## Contrast (WCAG 2.x, as text)

- On white (#ffffff): 6.06:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #485b60 (7.14:1)
- On black (#000000): 3.47:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #607980 (4.54:1); AA: background → #dedede (4.5:1); AAA: text → #829aa1 (7.09:1)

## Brands using this color

- **GitHub** — textMuted #57606a (Δ 1.855) — https://brandsweets.com/colors/brands/github

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/51666c-a2b5be-df4e75-1f242d-e9f1ef?lock=0&style=vibrant
(Humans lock/regenerate in the tool; the URL is the state — read `lock=` back to see what they kept.)

## Connect an agent

Point any MCP client at the BrandSweets colors endpoint for the same engine:

- Endpoint: https://mcp.brandsweets.com/colors/mcp
- Tools: `analyze_color` (e.g. `analyze_color({ color: "#51666c" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.