# #515781

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

## Values

- Hex: `#515781`
- RGB: rgb(81, 87, 129)
- HSL: hsl(233, 23%, 41%)
- OKLCH: oklch(0.47 0.068 277.2)
- Relative luminance: 0.1015
- Nearest named color: Dusk (#4e5481, Δ 1.042) — https://brandsweets.com/colors/dusk
- Moods: cool, muted
- Page: https://brandsweets.com/colors/515781

## Tints & shades

- Tints (toward white): #5c6393, #686fa1, #7b81ad, #8e93b8, #a1a5c4, #b1b4ce, #c3c6da, #d6d8e5, #e6e7ef, #f9f9fb
- Shades (toward black): #494e74, #43476b, #3b3f5e, #333752, #2d3048, #25283c, #1d202f, #161723, #101119, #08080d

## Harmonies

- Complementary: #817b51
- Analogous: #516e81, #635181
- Triadic: #815156, #568151
- Split-complementary: #816351, #6e8151
- Tetradic: #81516e, #817b51, #518163

## Colors that go with #515781

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 for #515781: softer than #000 and cool enough to feel like part of the same palette. Seen in: Harbour (https://brandsweets.com/palettes/cool#harbour), Amazon (https://brandsweets.com/colors/brands/amazon-com), Tumblr (https://brandsweets.com/colors/brands/tumblr-com), Codecademy (https://brandsweets.com/colors/brands/codecademy-com). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #515781 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Subaru (https://brandsweets.com/colors/brands/subaru-com), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Netflix (https://brandsweets.com/colors/brands/netflix), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com). — https://brandsweets.com/colors/seagreen
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #515781's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Capital One (https://brandsweets.com/colors/brands/capitalone-com), American Express (https://brandsweets.com/colors/brands/americanexpress-com), Discover (https://brandsweets.com/colors/brands/discover-com), Auth0 (https://brandsweets.com/colors/brands/auth0-com). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 5 real palettes, including Tesco's brand system and Activision's brand system put Blue beside #515781, as the supporting colour. Seen in: Tesco (https://brandsweets.com/colors/brands/tesco-com), Activision (https://brandsweets.com/colors/brands/activision-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Pixar (https://brandsweets.com/colors/brands/pixar-com). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #515781: 4 real palettes, including Fintech Trust and Unilever's brand system, as the lead colour. Seen in: Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Unilever (https://brandsweets.com/colors/brands/unilever-com), Ink & Paper (https://brandsweets.com/palettes/minimal#ink-and-paper), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/cobalt
- **Crimson** #dc143c [pool] — Crimson is paired with #515781 in 14 real palettes, including Wells Fargo's brand system and Walgreens's brand system, as the lead colour. Seen in: Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Codecademy (https://brandsweets.com/colors/brands/codecademy-com), Costco (https://brandsweets.com/colors/brands/costco-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #515781: 13 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), Dutch Bros (https://brandsweets.com/colors/brands/dutchbros-com), Costco (https://brandsweets.com/colors/brands/costco-com). — https://brandsweets.com/colors/denim
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #515781: 6 real palettes, including Campbell's's brand system and Fireside, as the supporting colour. Seen in: Campbell's (https://brandsweets.com/colors/brands/campbells-com), Fireside (https://brandsweets.com/palettes/dark#fireside), Wendy's (https://brandsweets.com/colors/brands/wendys-com), AT&T (https://brandsweets.com/colors/brands/att-com). — https://brandsweets.com/colors/firebrick

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

- On white (#ffffff): 6.93:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #4f547d (7.25:1)
- On black (#000000): 3.03:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #6c72a3 (4.57:1); AA: background → #d1d1d1 (4.54:1); AAA: text → #8e93b8 (7.02:1)

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/515781-9c9cc4-df884e-241f2d-e9eef1?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: "#515781" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.