# #3f439d

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

## Values

- Hex: `#3f439d`
- RGB: rgb(63, 67, 157)
- HSL: hsl(237, 43%, 43%)
- OKLCH: oklch(0.432 0.144 276.6)
- Relative luminance: 0.0751
- Nearest named color: Blueberry (#464196, Δ 1.55) — https://brandsweets.com/colors/blueberry
- Moods: cool, modern
- Page: https://brandsweets.com/colors/3f439d

## Tints & shades

- Tints (toward white): #474db3, #575cbc, #6d72c5, #7f83cc, #9598d5, #a7aadc, #bdbfe5, #d0d1ec, #e5e6f5, #f8f8fc
- Shades (toward black): #393d8e, #333780, #2d3071, #272a62, #232658, #1d1f49, #17193a, #11132c, #0c0d1d, #06060f

## Harmonies

- Complementary: #9d983f
- Analogous: #3f729d, #693f9d
- Triadic: #9d3f43, #439d3f
- Split-complementary: #9d693f, #729d3f
- Tetradic: #9d3f72, #9d983f, #3f9d69

## Colors that go with #3f439d

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 #3f439d: softer than #000 and cool enough to feel like part of the same palette. Seen in: Hasbro (https://brandsweets.com/colors/brands/hasbro-com), Amazon (https://brandsweets.com/colors/brands/amazon-com), dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Hinge (https://brandsweets.com/colors/brands/hinge-co). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #3f439d — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Intel (https://brandsweets.com/colors/brands/intel-com), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Netflix (https://brandsweets.com/colors/brands/netflix), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com). — https://brandsweets.com/colors/seagreen
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #3f439d'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), Glacier (https://brandsweets.com/palettes/cool#glacier), American Express (https://brandsweets.com/colors/brands/americanexpress-com), Hershey's (https://brandsweets.com/colors/brands/hersheys-com). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 7 real palettes, including CVS's brand system and Tesco's brand system put Blue beside #3f439d, as the supporting colour. Seen in: CVS (https://brandsweets.com/colors/brands/cvs-com), Tesco (https://brandsweets.com/colors/brands/tesco-com), Procter & Gamble (https://brandsweets.com/colors/brands/pg-com), Pixar (https://brandsweets.com/colors/brands/pixar-com). — https://brandsweets.com/colors/blue
- **Cornflower Blue** #6495ed [pool] — Designers have shipped Cornflower Blue with #3f439d: 4 real palettes, including Blue Mono and Gopro's brand system, as the supporting colour. Seen in: Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Gopro (https://brandsweets.com/colors/brands/gopro-com), Coca-Cola (https://brandsweets.com/colors/brands/coca-cola-com), Peacock (https://brandsweets.com/colors/brands/peacocktv-com). — https://brandsweets.com/colors/cornflowerblue
- **Crimson** #dc143c [pool] — Crimson is paired with #3f439d in 11 real palettes, including Walgreens's brand system and Wells Fargo's brand system, as the lead colour. Seen in: Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Costco (https://brandsweets.com/colors/brands/costco-com), Chase (https://brandsweets.com/colors/brands/chase-com). — https://brandsweets.com/colors/crimson
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #3f439d: 5 real palettes, including Datadog's brand system and MLB's brand system, as the accent. Seen in: Datadog (https://brandsweets.com/colors/brands/datadoghq-com), MLB (https://brandsweets.com/colors/brands/mlb-com), Campbell's (https://brandsweets.com/colors/brands/campbells-com), 3M (https://brandsweets.com/colors/brands/3m-com). — https://brandsweets.com/colors/firebrick
- **Midnight Blue** #191970 [pool] — 18 real palettes, including Blue Mono and Panasonic's brand system put Midnight Blue beside #3f439d, as that palette's text colour. Seen in: Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Panasonic (https://brandsweets.com/colors/brands/panasonic-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Air France (https://brandsweets.com/colors/brands/airfrance-com). — https://brandsweets.com/colors/midnightblue

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

- On white (#ffffff): 8.4:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.5:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #696ec3 (4.62:1); AA: background → #bfbfbf (4.57:1); AAA: text → #8e91d2 (7.13:1); AAA: background → #ebebeb (7.04:1)

## Fonts for this mood

- 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/3f439d-9f9cc4-df924e-251f2d-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: "#3f439d" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.