# #370a99

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

## Values

- Hex: `#370a99`
- RGB: rgb(55, 10, 153)
- HSL: hsl(259, 88%, 32%)
- OKLCH: oklch(0.347 0.197 283.3)
- Relative luminance: 0.0333
- Nearest named color: Dramatic Blue (#240093, Δ 4.052) — https://brandsweets.com/colors/dramatic-blue
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/370a99

## Tints & shades

- Tints (toward white): #430cbb, #4e0ed8, #5d19f0, #7136f2, #8957f4, #a179f6, #b596f8, #ccb7fa, #e1d4fc, #f8f5fe
- Shades (toward black): #32098b, #2d087d, #290773, #240665, #1f0656, #1a0548, #15043a, #110330, #0c0222, #070113

## Harmonies

- Complementary: #6c990a
- Analogous: #0a2499, #7f0a99
- Triadic: #99370a, #0a9937
- Split-complementary: #997f0a, #24990a
- Tetradic: #990a24, #6c990a, #0a997f

## Colors that go with #370a99

Named partners (harmony on the OKLCH wheel, co-occurrence in curated palettes and brand systems, and the neutrals that carry it), best first:

- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #370a99: 5 real palettes, including Tide's brand system and Purina Pro Plan's brand system, as the lead colour. Seen in: Tide (https://brandsweets.com/colors/brands/tide-com), Purina Pro Plan (https://brandsweets.com/colors/brands/chewy-com), Zillow (https://brandsweets.com/colors/brands/zillow-com), Unilever (https://brandsweets.com/colors/brands/unilever-com). — https://brandsweets.com/colors/cobalt
- **Crimson** #dc143c [pool] — Crimson is paired with #370a99 in 5 real palettes, including Pepsi's brand system and Casper Sleep's brand system, as the supporting colour. Seen in: Pepsi (https://brandsweets.com/colors/brands/pepsi-com), Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Nintendo (https://brandsweets.com/colors/brands/nintendo-com), Marvel (https://brandsweets.com/colors/brands/marvel-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [harmony, pool: analogous] — Denim is #370a99's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Warbyparker (https://brandsweets.com/colors/brands/warbyparker-com), Unilever (https://brandsweets.com/colors/brands/unilever-com), Bank of America (https://brandsweets.com/colors/brands/bankofamerica-com). — https://brandsweets.com/colors/denim
- **Royal Blue** #4169e1 [pool] — Royal Blue is paired with #370a99 in 5 real palettes, including Discord's brand system and Nivea's brand system, as the lead colour. Seen in: Discord (https://brandsweets.com/colors/brands/discord), Nivea (https://brandsweets.com/colors/brands/nivea-com), Nokia (https://brandsweets.com/colors/brands/nokia-com), NHL (https://brandsweets.com/colors/brands/nhl-com). — https://brandsweets.com/colors/royalblue
- **Steel Blue** #4682b4 [pool] — Designers have shipped Steel Blue with #370a99: 4 real palettes, including FedEx's brand system and Hershey's's brand system, as the accent. Seen in: FedEx (https://brandsweets.com/colors/brands/fedex-com), Hershey's (https://brandsweets.com/colors/brands/hersheys-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/steelblue
- **Olive Green** #808000 [harmony: complementary] — Olive Green sits directly opposite #370a99 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. — https://brandsweets.com/colors/olive
- **Blue** #0000ff [pool] — 3 real palettes, including Procter & Gamble's brand system and Zillow's brand system put Blue beside #370a99, as the supporting colour. Seen in: Procter & Gamble (https://brandsweets.com/colors/brands/pg-com), Zillow (https://brandsweets.com/colors/brands/zillow-com), Pfizer (https://brandsweets.com/colors/brands/pfizer-com). — https://brandsweets.com/colors/blue
- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black for #370a99: softer than #000 and cool enough to feel like part of the same palette. Seen in: dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Boeing (https://brandsweets.com/colors/brands/boeing-com). — https://brandsweets.com/colors/charcoal

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

- On white (#ffffff): 12.61:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.67:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #8652f4 (4.53:1); AA: background → #9c9c9c (4.59:1); AAA: text → #a782f7 (7.18:1); AAA: background → #c2c2c2 (7.08:1)

## Fonts for this mood

- technical: https://brandsweets.com/fonts/mood/technical
- 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/370a99-ad9cc4-dfc74e-2a1f2d-e9ebf1?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: "#370a99" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.