# #231d3f

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

## Values

- Hex: `#231d3f`
- RGB: rgb(35, 29, 63)
- HSL: hsl(251, 37%, 18%)
- OKLCH: oklch(0.257 0.062 289.4)
- Relative luminance: 0.0159
- Nearest named color: Black Market (#222244, Δ 1.657) — https://brandsweets.com/colors/black-market
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/231d3f

## Tints & shades

- Tints (toward white): #332a5b, #423777, #524393, #6250af, #7b6cbc, #9488c8, #ada4d5, #c6c0e2, #e0dcef, #f9f8fc
- Shades (toward black): #211b3b, #1d1834, #1b1631, #17132a, #151226, #141023, #100d1c, #0e0b18, #0a0811, #08060e

## Harmonies

- Complementary: #393f1d
- Analogous: #1d283f, #341d3f
- Triadic: #3f231d, #1d3f23
- Split-complementary: #3f341d, #283f1d
- Tetradic: #3f1d28, #393f1d, #1d3f34

## Colors that go with #231d3f

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 #231d3f: softer than #000 and cool enough to feel like part of the same palette. Seen in: Volkswagen (https://brandsweets.com/colors/brands/vw-com), Microsoft (https://brandsweets.com/colors/brands/microsoft-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 #231d3f on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: 7-Eleven (https://brandsweets.com/colors/brands/7-eleven-com), Cohere (https://brandsweets.com/colors/brands/cohere-com), Warp (https://brandsweets.com/colors/brands/warp-dev), Oatmeal (https://brandsweets.com/palettes/neutral#oatmeal). — https://brandsweets.com/colors/darkolivegreen
- **Sea Green** #2e8b57 [harmony, pool: split] — Sea Green is a split-complement of #231d3f: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Subaru (https://brandsweets.com/colors/brands/subaru-com), Asana (https://brandsweets.com/colors/brands/asana-com), Wellness (https://brandsweets.com/palettes/warm#wellness), Mushroom (https://brandsweets.com/palettes/neutral#mushroom). — https://brandsweets.com/colors/seagreen
- **Sienna** #a0522d [harmony, pool: split] — Sienna is a split-complement of #231d3f: 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), Olive Grove (https://brandsweets.com/palettes/muted#olive-grove), Harvest (https://brandsweets.com/palettes/warm#harvest). — https://brandsweets.com/colors/sienna
- **Slate Blue** #6a5acd [harmony, pool: analogous] — Slate Blue is #231d3f'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), GitLab (https://brandsweets.com/colors/brands/gitlab), Superhuman (https://brandsweets.com/colors/brands/superhuman-com), Sentry (https://brandsweets.com/colors/brands/sentry-io). — https://brandsweets.com/colors/slateblue
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #231d3f's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Discover (https://brandsweets.com/colors/brands/discover-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Plaid (https://brandsweets.com/colors/brands/plaid-com). — https://brandsweets.com/colors/steelblue
- **Teal** #008080 [harmony, pool: triadic] — Teal completes a triad with #231d3f — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Alpine (https://brandsweets.com/palettes/cool#alpine), Clinic (https://brandsweets.com/palettes/clean#clinic), Lufthansa (https://brandsweets.com/colors/brands/lufthansa-com), Sapphire & Gold (https://brandsweets.com/palettes/luxury#sapphire-and-gold). — https://brandsweets.com/colors/teal
- **Amber** #ffbf00 [pool] — Amber is paired with #231d3f in 18 real palettes, including Southwest Airlines's brand system and Beach Hut, as the accent. Seen in: Southwest Airlines (https://brandsweets.com/colors/brands/southwest-com), Beach Hut (https://brandsweets.com/palettes/light#beach-hut), Blueprint (https://brandsweets.com/palettes/technical#blueprint), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org). — https://brandsweets.com/colors/amber

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

- On white (#ffffff): 15.92:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.32:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #7869ba (4.53:1); AA: background → #8a8a8a (4.61:1); AAA: text → #9a8fcc (7.17:1); AAA: background → #adadad (7.09:1)

## Brands using this color

- **Discover** — primary #23233f (Δ 1.907) — https://brandsweets.com/colors/brands/discover-com

## 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/231d3f-a89cc4-dfb34e-281f2d-e9ecf1?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: "#231d3f" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.