# #1f3370

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

## Values

- Hex: `#1f3370`
- RGB: rgb(31, 51, 112)
- HSL: hsl(225, 57%, 28%)
- OKLCH: oklch(0.342 0.109 266.9)
- Relative luminance: 0.0383
- Nearest named color: Atlantic Navy (#13336f, Δ 1.23) — https://brandsweets.com/colors/atlantic-navy
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/1f3370

## Tints & shades

- Tints (toward white): #26408c, #2e4da8, #3659c4, #4f6fcf, #6b86d6, #879dde, #a3b4e6, #bfcbed, #dbe2f5, #f7f8fd
- Shades (toward black): #1d2f68, #192a5c, #172654, #142148, #121d40, #0f1a38, #0c142c, #0a1024, #070b18, #040710

## Harmonies

- Complementary: #705c1f
- Analogous: #1f5c70, #331f70
- Triadic: #701f33, #33701f
- Split-complementary: #70331f, #5c701f
- Tetradic: #701f5c, #705c1f, #1f7033

## Colors that go with #1f3370

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

- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #1f3370's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Plaid (https://brandsweets.com/colors/brands/plaid-com), Glacier (https://brandsweets.com/palettes/cool#glacier), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Hershey's (https://brandsweets.com/colors/brands/hersheys-com). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 8 real palettes, including Alaska Airlines's brand system and Procter & Gamble's brand system put Blue beside #1f3370, as the accent. Seen in: Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), Procter & Gamble (https://brandsweets.com/colors/brands/pg-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Sketch (https://brandsweets.com/colors/brands/sketch-com). — https://brandsweets.com/colors/blue
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #1f3370: 4 real palettes, including Open House and Coastal, as the supporting colour. Seen in: Open House (https://brandsweets.com/palettes/clean#open-house), Coastal (https://brandsweets.com/palettes/cool#coastal), SoFi (https://brandsweets.com/colors/brands/sofi-com), Dusk (https://brandsweets.com/palettes/cool#dusk). — https://brandsweets.com/colors/cadetblue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #1f3370: 4 real palettes, including Purina Pro Plan's brand system and Blue Mono, as the accent. Seen in: Purina Pro Plan (https://brandsweets.com/colors/brands/chewy-com), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Unilever (https://brandsweets.com/colors/brands/unilever-com), MLB (https://brandsweets.com/colors/brands/mlb-com). — https://brandsweets.com/colors/cobalt
- **Crimson** #dc143c [pool] — Crimson is paired with #1f3370 in 7 real palettes, including Casper Sleep's brand system and Marvel's brand system, as the lead colour. Seen in: Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Marvel (https://brandsweets.com/colors/brands/marvel-com), Nintendo (https://brandsweets.com/colors/brands/nintendo-com), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember). — https://brandsweets.com/colors/crimson
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #1f3370: 4 real palettes, including Lamborghini's brand system and Kraken's brand system, as the supporting colour. Seen in: Lamborghini (https://brandsweets.com/colors/brands/lamborghini-com), Kraken (https://brandsweets.com/colors/brands/kraken-com), Vimeo (https://brandsweets.com/colors/brands/vimeo-com), Astro (https://brandsweets.com/colors/brands/astro-build). — https://brandsweets.com/colors/deepskyblue
- **Denim** #1560bd [pool] — Designers have shipped Denim with #1f3370: 18 real palettes, including Hasbro's brand system and Panasonic's brand system, as the supporting colour. Seen in: Hasbro (https://brandsweets.com/colors/brands/hasbro-com), Panasonic (https://brandsweets.com/colors/brands/panasonic-com), Bank of America (https://brandsweets.com/colors/brands/bankofamerica-com), Hinge (https://brandsweets.com/colors/brands/hinge-co). — https://brandsweets.com/colors/denim
- **White Smoke** #f5f5f5 [role] — White Smoke is the surface for #1f3370: a clean near-white with no warm cast, so the cool hue stays clear instead of drifting muddy. — https://brandsweets.com/colors/whitesmoke

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

- On white (#ffffff): 11.89:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.77:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #4f6fcf (4.51:1); AA: background → #a1a1a1 (4.6:1); AAA: text → #7b93db (7.04:1); AAA: background → #c7c7c7 (7.04:1)

## Brands using this color

- **Casper Sleep** — accent #1e306e (Δ 0.921) — https://brandsweets.com/colors/brands/casper-com
- **Gillette** — accent #182f6e (Δ 1.529) — https://brandsweets.com/colors/brands/gillette-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/1f3370-9ca1c4-df754e-221f2d-e9eff1?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: "#1f3370" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.