# #515b7b

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

## Values

- Hex: `#515b7b`
- RGB: rgb(81, 91, 123)
- HSL: hsl(226, 21%, 40%)
- OKLCH: oklch(0.476 0.053 270.9)
- Relative luminance: 0.1066
- Nearest named color: Deep Indigo (#4c567a, Δ 1.729) — https://brandsweets.com/colors/deep-indigo
- Moods: cool, muted
- Page: https://brandsweets.com/colors/515b7b

## Tints & shades

- Tints (toward white): #5d688e, #6b779e, #7a85a8, #8d96b4, #9fa7c1, #b2b8cd, #c4c9d9, #d4d7e3, #e6e8ef, #f9f9fb
- Shades (toward black): #49526f, #424b66, #3a4259, #343b50, #2c3244, #242938, #1e222e, #161922, #101219, #08090c

## Harmonies

- Complementary: #7b7151
- Analogous: #51707b, #5c517b
- Triadic: #7b515b, #5b7b51
- Split-complementary: #7b5c51, #707b51
- Tetradic: #7b5170, #7b7151, #517b5c

## Colors that go with #515b7b

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 #515b7b: 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), Pampers (https://brandsweets.com/colors/brands/pampers-com). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #515b7b — 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), Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com), Netflix (https://brandsweets.com/colors/brands/netflix). — https://brandsweets.com/colors/seagreen
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #515b7b'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
- **Blue** #0000ff [pool] — 4 real palettes, including Activision's brand system and Tesco's brand system put Blue beside #515b7b, as the accent. Seen in: Activision (https://brandsweets.com/colors/brands/activision-com), Tesco (https://brandsweets.com/colors/brands/tesco-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 #515b7b: 4 real palettes, including Fintech Trust and Ink & Paper, as the lead colour. Seen in: Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Ink & Paper (https://brandsweets.com/palettes/minimal#ink-and-paper), Unilever (https://brandsweets.com/colors/brands/unilever-com), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/cobalt
- **Copper** #b87333 [pool] — Designers have shipped Copper with #515b7b: 4 real palettes, including Dusk and Desert Road, as the accent. Seen in: Dusk (https://brandsweets.com/palettes/cool#dusk), Desert Road (https://brandsweets.com/palettes/warm#desert-road), Riverbed (https://brandsweets.com/palettes/muted#riverbed), Clay & Linen (https://brandsweets.com/palettes/warm#clay-and-linen). — https://brandsweets.com/colors/copper
- **Crimson** #dc143c [pool] — Crimson is paired with #515b7b in 15 real palettes, including Codecademy's brand system and Wells Fargo's brand system, as the accent. Seen in: Codecademy (https://brandsweets.com/colors/brands/codecademy-com), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Costco (https://brandsweets.com/colors/brands/costco-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #515b7b: 15 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), Campus (https://brandsweets.com/palettes/friendly#campus). — https://brandsweets.com/colors/denim

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

- On white (#ffffff): 6.7:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #4f5878 (7:1)
- On black (#000000): 3.13:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #68749c (4.57:1); AA: background → #d4d4d4 (4.52:1); AAA: text → #8d96b4 (7.15:1)

## Brands using this color

- **Stripe** — secondary #50617a (Δ 1.865) — https://brandsweets.com/colors/brands/stripe

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/515b7b-9ca1c4-df774e-221f2d-e9eff1?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: "#515b7b" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.