# #100d4f

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

## Values

- Hex: `#100d4f`
- RGB: rgb(16, 13, 79)
- HSL: hsl(243, 72%, 18%)
- OKLCH: oklch(0.224 0.114 274.1)
- Relative luminance: 0.0096
- Nearest named color: Ravenclaw (#0a0555, Δ 2.036) — https://brandsweets.com/colors/ravenclaw
- Moods: cool, vivid, dark, technical, modern, luxury, bold
- Page: https://brandsweets.com/colors/100d4f

## Tints & shades

- Tints (toward white): #171372, #1f1895, #261eb8, #2d24db, #4e47e1, #706ae7, #928dec, #b3b0f2, #d5d3f8, #f7f6fe
- Shades (toward black): #0f0c4b, #0d0b42, #0d0a3d, #0b0935, #0a0830, #09072c, #070623, #06051f, #040416, #040312

## Harmonies

- Complementary: #4c4f0d
- Analogous: #0d2b4f, #310d4f
- Triadic: #4f100d, #0d4f10
- Split-complementary: #4f310d, #2b4f0d
- Tetradic: #4f0d2b, #4c4f0d, #0d4f31

## Colors that go with #100d4f

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 #100d4f: softer than #000 and cool enough to feel like part of the same palette. Seen in: Plaid (https://brandsweets.com/colors/brands/plaid-com), 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). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #100d4f — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com), Intel (https://brandsweets.com/colors/brands/intel-com), Asana (https://brandsweets.com/colors/brands/asana-com), Kia (https://brandsweets.com/colors/brands/kia-com). — https://brandsweets.com/colors/seagreen
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #100d4f's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Deep Water (https://brandsweets.com/palettes/dark#deep-water), Glacier (https://brandsweets.com/palettes/cool#glacier), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Plaid (https://brandsweets.com/colors/brands/plaid-com). — https://brandsweets.com/colors/steelblue
- **Amber** #ffbf00 [pool] — Amber is paired with #100d4f in 7 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), Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 11 real palettes, including Penpot's brand system and Monzo's brand system put Blue beside #100d4f, as the supporting colour. Seen in: Penpot (https://brandsweets.com/colors/brands/penpot-app), Monzo (https://brandsweets.com/colors/brands/monzo-com), League of Legends (https://brandsweets.com/colors/brands/leagueoflegends-com), Sketch (https://brandsweets.com/colors/brands/sketch-com). — https://brandsweets.com/colors/blue
- **Blue Violet** #8a2be2 [harmony, pool: analogous] — Blue Violet is #100d4f's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Gemstone (https://brandsweets.com/palettes/vivid#gemstone), Yahoo (https://brandsweets.com/colors/brands/yahoo-com), ClickUp (https://brandsweets.com/colors/brands/clickup-com). — https://brandsweets.com/colors/blueviolet
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #100d4f: 9 real palettes, including SoFi's brand system and Arctic, as the supporting colour. Seen in: SoFi (https://brandsweets.com/colors/brands/sofi-com), Arctic (https://brandsweets.com/palettes/clean#arctic), Alpine (https://brandsweets.com/palettes/cool#alpine), Open House (https://brandsweets.com/palettes/clean#open-house). — https://brandsweets.com/colors/cadetblue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #100d4f: 13 real palettes, including Glacier and Air France's brand system, as the accent. Seen in: Glacier (https://brandsweets.com/palettes/cool#glacier), Air France (https://brandsweets.com/colors/brands/airfrance-com), MLB (https://brandsweets.com/colors/brands/mlb-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust). — https://brandsweets.com/colors/cobalt

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

- On white (#ffffff): 17.61:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.19:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #6c65e6 (4.64:1); AA: background → #828282 (4.58:1); AAA: text → #928dec (7.24:1); AAA: background → #a6a6a6 (7.23:1)

## Brands using this color

- **Railway** — primary #13044c (Δ 1.808) — https://brandsweets.com/colors/brands/railway-app

## Fonts for this mood

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

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/100d4f-a39cc4-dfa04e-261f2d-e9edf1?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: "#100d4f" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.