# #b40421

A color — warm, vivid, playful, bold. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#b40421`
- RGB: rgb(180, 4, 33)
- HSL: hsl(350, 96%, 36%)
- OKLCH: oklch(0.487 0.195 23.8)
- Relative luminance: 0.099
- Nearest named color: All Systems Red (#b30103, Δ 1.819) — https://brandsweets.com/colors/all-systems-red
- Moods: warm, vivid, playful, bold
- Page: https://brandsweets.com/colors/b40421

## Tints & shades

- Tints (toward white): #d20427, #f0052c, #fa1e43, #fb3c5c, #fc5a75, #fc788e, #fd96a7, #feb9c4, #fed7de, #fff5f7
- Shades (toward black): #a5031e, #96031c, #820318, #730215, #640212, #550210, #46010d, #320109, #230106, #140004

## Harmonies

- Complementary: #04b497
- Analogous: #b40479, #b43e04
- Triadic: #21b404, #0421b4
- Split-complementary: #04b43e, #0479b4
- Tetradic: #79b404, #04b497, #3e04b4

## Colors that go with #b40421

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

- **Royal Blue** #4169e1 [harmony, pool: triadic] — Royal Blue completes a triad with #b40421 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Bose (https://brandsweets.com/colors/brands/bose-com), Behance (https://brandsweets.com/colors/brands/behance-net), Coinbase (https://brandsweets.com/colors/brands/coinbase), Chase (https://brandsweets.com/colors/brands/chase-com). — https://brandsweets.com/colors/royalblue
- **Steel Blue** #4682b4 [harmony, pool: split] — Steel Blue is a split-complement of #b40421: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Wendy's (https://brandsweets.com/colors/brands/wendys-com), Honda (https://brandsweets.com/colors/brands/honda-com), NASCAR (https://brandsweets.com/colors/brands/nascar-com), Wired (https://brandsweets.com/colors/brands/wired-com). — https://brandsweets.com/colors/steelblue
- **Teal** #008080 [harmony, pool: complementary] — Teal sits directly opposite #b40421 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Redfin (https://brandsweets.com/colors/brands/redfin-com), Gemstone (https://brandsweets.com/palettes/vivid#gemstone), Magazine Ochre (https://brandsweets.com/palettes/editorial#magazine-ochre), Saffron (https://brandsweets.com/palettes/warm#saffron). — https://brandsweets.com/colors/teal
- **Amber** #ffbf00 [pool] — Amber is paired with #b40421 in 5 real palettes, including Maple and Ember, as the accent. Seen in: Maple (https://brandsweets.com/palettes/warm#maple), Ember (https://brandsweets.com/palettes/bold#ember), Trailhead (https://brandsweets.com/palettes/warm#trailhead), McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 4 real palettes, including Tim Hortons's brand system and Dunkin''s brand system put Blue beside #b40421, as the accent. Seen in: Tim Hortons (https://brandsweets.com/colors/brands/timhortons-com), Dunkin' (https://brandsweets.com/colors/brands/dunkindonuts-com), native Cybersecurity (https://brandsweets.com/colors/brands/crowdstrike-com), Doordash (https://brandsweets.com/colors/brands/doordash-com). — https://brandsweets.com/colors/blue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #b40421: 4 real palettes, including MLB's brand system and Behance's brand system, as the accent. Seen in: MLB (https://brandsweets.com/colors/brands/mlb-com), Behance (https://brandsweets.com/colors/brands/behance-net), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Reebok (https://brandsweets.com/colors/brands/reebok-com). — https://brandsweets.com/colors/cobalt
- **Dark Olive Green** #556b2f [pool] — Dark Olive Green shows up next to #b40421 in 4 real palettes, including Olive Grove and Cider, as the lead colour. Seen in: Olive Grove (https://brandsweets.com/palettes/muted#olive-grove), Cider (https://brandsweets.com/palettes/warm#cider), BrandSweets (https://brandsweets.com/colors/brands/brandsweets), Magazine Ochre (https://brandsweets.com/palettes/editorial#magazine-ochre). — https://brandsweets.com/colors/darkolivegreen
- **Charcoal** #36454f [role, pool] — Charcoal is the body-text near-black for #b40421: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy. Seen in: IHG (https://brandsweets.com/colors/brands/ihg-com), Codecademy (https://brandsweets.com/colors/brands/codecademy-com). — https://brandsweets.com/colors/charcoal

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

- On white (#ffffff): 7.05:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.98:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #eb052b (4.59:1); AA: background → #cfcfcf (4.52:1); AAA: text → #fc5f79 (7.05:1); AAA: background → #ffffff (7.05:1)

## Brands using this color

- **Twilio** — accent #b10f23 (Δ 0.656) — https://brandsweets.com/colors/brands/twilio-com
- **Wendy's** — secondary #b0161f (Δ 1.169) — https://brandsweets.com/colors/brands/wendys-com
- **In-N-Out Burger** — secondary #b60000 (Δ 1.925) — https://brandsweets.com/colors/brands/in-n-out-com

## Fonts for this mood

- warm: https://brandsweets.com/fonts/mood/warm
- playful: https://brandsweets.com/fonts/mood/playful
- 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/b40421-c49c9e-62cb87-2d231f-f1e9ee?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: "#b40421" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.