# #555b77

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

## Values

- Hex: `#555b77`
- RGB: rgb(85, 91, 119)
- HSL: hsl(229, 17%, 40%)
- OKLCH: oklch(0.477 0.046 275.1)
- Relative luminance: 0.1075
- Nearest named color: Deep Indigo (#4c567a, Δ 2.261) — https://brandsweets.com/colors/deep-indigo
- Moods: cool, muted
- Page: https://brandsweets.com/colors/555b77

## Tints & shades

- Tints (toward white): #616989, #707799, #7f86a4, #9196b1, #a3a7bd, #b4b8ca, #c6c9d7, #d5d7e1, #e7e8ee, #f9f9fb
- Shades (toward black): #4c526b, #464b62, #3d4257, #373b4e, #2f3242, #262936, #20222d, #171921, #111218, #08090c

## Harmonies

- Complementary: #777155
- Analogous: #556c77, #605577
- Triadic: #77555b, #5b7755
- Split-complementary: #776055, #6c7755
- Tetradic: #77556c, #777155, #557760

## Colors that go with #555b77

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 #555b77: softer than #000 and cool enough to feel like part of the same palette. Seen in: Harbour (https://brandsweets.com/palettes/cool#harbour), Campus (https://brandsweets.com/palettes/friendly#campus), Amazon (https://brandsweets.com/colors/brands/amazon-com), 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 #555b77 — 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 #555b77'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), Auth0 (https://brandsweets.com/colors/brands/auth0-com), American Express (https://brandsweets.com/colors/brands/americanexpress-com). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 5 real palettes, including Activision's brand system and Tesco's brand system put Blue beside #555b77, 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 #555b77: 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 #555b77: 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), 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 #555b77 in 14 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), Retro Pop (https://brandsweets.com/palettes/playful#retro-pop), Wendy's (https://brandsweets.com/colors/brands/wendys-com). — https://brandsweets.com/colors/crimson
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #555b77: 4 real palettes, including Lamborghini's brand system and Venmo's brand system, as the supporting colour. Seen in: Lamborghini (https://brandsweets.com/colors/brands/lamborghini-com), Venmo (https://brandsweets.com/colors/brands/venmo-com), Deep Water (https://brandsweets.com/palettes/dark#deep-water), Warp (https://brandsweets.com/colors/brands/warp-dev). — https://brandsweets.com/colors/deepskyblue

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

- On white (#ffffff): 6.67:1 — AA pass, AA-large pass, AAA fail. Fix: AAA: text → #505671 (7.21:1)
- On black (#000000): 3.15:1 — AA fail, AA-large pass, AAA fail. Fix: AA: text → #6d7597 (4.64:1); AA: background → #d6d6d6 (4.59:1); AAA: text → #8e94af (7.01:1)

## Brands using this color

- **Stripe** — secondary #50617a (Δ 1.776) — https://brandsweets.com/colors/brands/stripe

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/555b77-9c9fc4-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: "#555b77" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.