# #515b8a

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

## Values

- Hex: `#515b8a`
- RGB: rgb(81, 91, 138)
- HSL: hsl(229, 26%, 43%)
- OKLCH: oklch(0.483 0.077 274)
- Relative luminance: 0.1107
- Nearest named color: Dusk (#4e5481, Δ 2.333) — https://brandsweets.com/colors/dusk
- Moods: cool, muted
- Page: https://brandsweets.com/colors/515b8a

## Tints & shades

- Tints (toward white): #5c689d, #6b76a8, #7e88b4, #8f97bd, #a2a9c8, #b2b8d2, #c5cadd, #d5d8e6, #e9eaf2, #f9f9fb
- Shades (toward black): #4a537d, #424b70, #3a4264, #333a57, #2d334d, #262b40, #1e2233, #171a27, #0f111a, #08090d

## Harmonies

- Complementary: #8a8051
- Analogous: #51788a, #63518a
- Triadic: #8a515c, #5c8a51
- Split-complementary: #8a6351, #788a51
- Tetradic: #8a5178, #8a8051, #518a63

## Colors that go with #515b8a

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 #515b8a: 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), Campus (https://brandsweets.com/palettes/friendly#campus), Hinge (https://brandsweets.com/colors/brands/hinge-co). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #515b8a — 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 #515b8a'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), Discover (https://brandsweets.com/colors/brands/discover-com), American Express (https://brandsweets.com/colors/brands/americanexpress-com), Auth0 (https://brandsweets.com/colors/brands/auth0-com). — https://brandsweets.com/colors/steelblue
- **Amber** #ffbf00 [pool] — Amber is paired with #515b8a in 5 real palettes, including McDonald's's brand system and Warner Bros.'s brand system, as the lead colour. Seen in: McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com), Warner Bros. (https://brandsweets.com/colors/brands/warnerbros-com), Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 4 real palettes, including Activision's brand system and Tesco's brand system put Blue beside #515b8a, as the accent. Seen in: Activision (https://brandsweets.com/colors/brands/activision-com), Tesco (https://brandsweets.com/colors/brands/tesco-com), Pixar (https://brandsweets.com/colors/brands/pixar-com), CVS (https://brandsweets.com/colors/brands/cvs-com). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #515b8a: 6 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 #515b8a in 16 real palettes, including Wells Fargo's brand system and Costco's brand system, as the lead colour. Seen in: Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Costco (https://brandsweets.com/colors/brands/costco-com), McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com). — https://brandsweets.com/colors/crimson
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #515b8a: 4 real palettes, including Venmo's brand system and Deep Water, as the supporting colour. Seen in: Venmo (https://brandsweets.com/colors/brands/venmo-com), Deep Water (https://brandsweets.com/palettes/dark#deep-water), Astro (https://brandsweets.com/colors/brands/astro-build), Lamborghini (https://brandsweets.com/colors/brands/lamborghini-com). — https://brandsweets.com/colors/deepskyblue

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

- On white (#ffffff): 6.54:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #4b5581 (7.2:1)
- On black (#000000): 3.21:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #6873a6 (4.59:1); AA: background → #d9d9d9 (4.63:1); AAA: text → #8b94bb (7.05:1)

## Curated palettes containing it

- **Dusk** (cool, muted, elegant) — #4b5d8a, #8b97b3, #c07a4e, #eef0f4, #1f2430 — Slate blue with a copper accent — calm, professional, slightly editorial; suits consultancies and journals. — tool: https://brandsweets.com/palettes/new/4b5d8a-8b97b3-c07a4e-eef0f4-1f2430 — collection: https://brandsweets.com/palettes/cool

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/515b8a-9c9fc4-df7e4e-231f2d-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: "#515b8a" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.