# #151d41

A color — cool, dark, luxury, bold, modern. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#151d41`
- RGB: rgb(21, 29, 65)
- HSL: hsl(229, 51%, 17%)
- OKLCH: oklch(0.246 0.069 271.1)
- Relative luminance: 0.0142
- Nearest named color: Nightwalker (#161d3b, Δ 1.149) — https://brandsweets.com/colors/nightwalker
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/151d41

## Tints & shades

- Tints (toward white): #1f2b60, #29397f, #33479e, #3d55bd, #5d71cb, #7c8cd5, #9ba7df, #bac2e9, #d8ddf3, #f7f8fd
- Shades (toward black): #141c3e, #111836, #101632, #0f152e, #0e132a, #0b1023, #0a0e1f, #090c1b, #060913, #05070f

## Harmonies

- Complementary: #413915
- Analogous: #153341, #231541
- Triadic: #41151d, #1d4115
- Split-complementary: #412315, #334115
- Tetradic: #411533, #413915, #154123

## Colors that go with #151d41

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 #151d41: softer than #000 and cool enough to feel like part of the same palette. Seen in: Microsoft (https://brandsweets.com/colors/brands/microsoft-com), Volkswagen (https://brandsweets.com/colors/brands/vw-com), Tide Pool (https://brandsweets.com/palettes/cool#tide-pool), Plaid (https://brandsweets.com/colors/brands/plaid-com). — https://brandsweets.com/colors/charcoal
- **Dark Olive Green** #556b2f [harmony, pool: complementary] — Dark Olive Green sits directly opposite #151d41 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Cohere (https://brandsweets.com/colors/brands/cohere-com), Warp (https://brandsweets.com/colors/brands/warp-dev), 7-Eleven (https://brandsweets.com/colors/brands/7-eleven-com), Oatmeal (https://brandsweets.com/palettes/neutral#oatmeal). — https://brandsweets.com/colors/darkolivegreen
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #151d41 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Asana (https://brandsweets.com/colors/brands/asana-com), Subaru (https://brandsweets.com/colors/brands/subaru-com), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com), Kia (https://brandsweets.com/colors/brands/kia-com). — https://brandsweets.com/colors/seagreen
- **Sienna** #a0522d [harmony, pool: split] — Sienna is a split-complement of #151d41: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Woodsmoke (https://brandsweets.com/palettes/dark#woodsmoke), BrandSweets (https://brandsweets.com/colors/brands/brandsweets), Coffee Bar (https://brandsweets.com/palettes/dark#coffee-bar), Olive Grove (https://brandsweets.com/palettes/muted#olive-grove). — https://brandsweets.com/colors/sienna
- **Slate Blue** #6a5acd [harmony, pool: analogous] — Slate Blue is #151d41's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Indigo SaaS (https://brandsweets.com/palettes/modern#indigo-saas), Sentry (https://brandsweets.com/colors/brands/sentry-io), GitLab (https://brandsweets.com/colors/brands/gitlab), Superhuman (https://brandsweets.com/colors/brands/superhuman-com). — https://brandsweets.com/colors/slateblue
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #151d41's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Discover (https://brandsweets.com/colors/brands/discover-com), Plaid (https://brandsweets.com/colors/brands/plaid-com), Beach Hut (https://brandsweets.com/palettes/light#beach-hut). — https://brandsweets.com/colors/steelblue
- **Amber** #ffbf00 [pool] — Amber is paired with #151d41 in 18 real palettes, including Southwest Airlines's brand system and Blueprint, as the accent. Seen in: Southwest Airlines (https://brandsweets.com/colors/brands/southwest-com), Blueprint (https://brandsweets.com/palettes/technical#blueprint), Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 20 real palettes, including Monzo's brand system and Sketch's brand system put Blue beside #151d41, as the accent. Seen in: Monzo (https://brandsweets.com/colors/brands/monzo-com), Sketch (https://brandsweets.com/colors/brands/sketch-com), Penpot (https://brandsweets.com/colors/brands/penpot-app), League of Legends (https://brandsweets.com/colors/brands/leagueoflegends-com). — https://brandsweets.com/colors/blue

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

- On white (#ffffff): 16.36:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.28:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #5d71cb (4.69:1); AA: background → #878787 (4.55:1); AAA: text → #8493d7 (7.14:1); AAA: background → #ababab (7.12:1)

## Brands using this color

- **Southwest Airlines** — secondary #111b40 (Δ 0.942) — https://brandsweets.com/colors/brands/southwest-com
- **MLB** — primary #041e42 (Δ 1.961) — https://brandsweets.com/colors/brands/mlb-com

## Curated palettes containing it

- **Telehealth** (modern, cool, friendly) — #2563eb, #93c5fd, #16a34a, #ffffff, #14213d — Friendly blue with a soft tint and a green all-clear — approachable care with a tech backbone. — tool: https://brandsweets.com/palettes/new/2563eb-93c5fd-16a34a-ffffff-14213d — collection: https://brandsweets.com/palettes/modern
- **First Snow** (winter, cool, light, minimal) — #2b4c7e, #8fa8c8, #c9d6e3, #fbfcfe, #14213d — Ice blue on snow-white with a deep navy — the quietest winter palette; everything is a tint of one cold hue. — tool: https://brandsweets.com/palettes/new/2b4c7e-8fa8c8-c9d6e3-fbfcfe-14213d — collection: https://brandsweets.com/palettes/winter

## Fonts for this mood

- luxury: https://brandsweets.com/fonts/mood/luxury
- bold: https://brandsweets.com/fonts/mood/bold
- modern: https://brandsweets.com/fonts/mood/modern

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/151d41-9c9fc4-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: "#151d41" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.