# #040d1b

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

## Values

- Hex: `#040d1b`
- RGB: rgb(4, 13, 27)
- HSL: hsl(217, 74%, 6%)
- OKLCH: oklch(0.158 0.034 256)
- Relative luminance: 0.0039
- Nearest named color: Dark Rift (#060b14, Δ 1.542) — https://brandsweets.com/colors/dark-rift
- Moods: cool, vivid, dark, technical, modern, luxury, bold
- Page: https://brandsweets.com/colors/040d1b

## Tints & shades

- Tints (toward white): #0a2043, #10336a, #174897, #1d5bbf, #2a6fdf, #528ae5, #7aa5eb, #a6c3f2, #cedef8, #f6f9fe
- Shades (toward black): #040d1b, #040d1b, #030b16, #030b16, #030b16, #030b16, #030b16, #030812, #030812, #030812

## Harmonies

- Complementary: #1b1204
- Analogous: #04181b, #07041b
- Triadic: #1b040d, #0d1b04
- Split-complementary: #1b0704, #181b04
- Tetradic: #1b0418, #1b1204, #041b07

## Colors that go with #040d1b

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 #040d1b: softer than #000 and cool enough to feel like part of the same palette. Seen in: Asana (https://brandsweets.com/colors/brands/asana-com), Amazon (https://brandsweets.com/colors/brands/amazon-com), Bloomberg (https://brandsweets.com/colors/brands/bloomberg-com), Codecademy (https://brandsweets.com/colors/brands/codecademy-com). — https://brandsweets.com/colors/charcoal
- **Rust** #b7410e [harmony, pool: triadic] — Rust completes a triad with #040d1b — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Noir Beauty (https://brandsweets.com/palettes/dark#noir-beauty), Semrush (https://brandsweets.com/colors/brands/semrush-com), Wayfair (https://brandsweets.com/colors/brands/wayfair-com), Garnet (https://brandsweets.com/palettes/warm#garnet). — https://brandsweets.com/colors/rust
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #040d1b — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Kia (https://brandsweets.com/colors/brands/kia-com), Intel (https://brandsweets.com/colors/brands/intel-com), Coinbase (https://brandsweets.com/colors/brands/coinbase), Asana (https://brandsweets.com/colors/brands/asana-com). — https://brandsweets.com/colors/seagreen
- **Sienna** #a0522d [harmony, pool: complementary] — Sienna sits directly opposite #040d1b on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Oatly (https://brandsweets.com/colors/brands/oatly-com), Coffee Bar (https://brandsweets.com/palettes/dark#coffee-bar), Woodsmoke (https://brandsweets.com/palettes/dark#woodsmoke), BrandSweets (https://brandsweets.com/colors/brands/brandsweets). — https://brandsweets.com/colors/sienna
- **Slate Blue** #6a5acd [harmony, pool: analogous] — Slate Blue is #040d1b's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Linear (https://brandsweets.com/colors/brands/linear), Calm (https://brandsweets.com/colors/brands/calm-com), Marvel (https://brandsweets.com/colors/brands/marvel-com), Sentry (https://brandsweets.com/colors/brands/sentry-io). — https://brandsweets.com/colors/slateblue
- **Teal** #008080 [harmony, pool: analogous] — Teal is #040d1b'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), Redfin (https://brandsweets.com/colors/brands/redfin-com), Perplexity (https://brandsweets.com/colors/brands/perplexity), Clinic (https://brandsweets.com/palettes/clean#clinic). — https://brandsweets.com/colors/teal
- **Amber** #ffbf00 [pool] — Amber is paired with #040d1b in 16 real palettes, including Southwest Airlines's brand system and Lemon Squeezy's brand system, as the accent. Seen in: Southwest Airlines (https://brandsweets.com/colors/brands/southwest-com), Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com), Ahrefs (https://brandsweets.com/colors/brands/ahrefs-com), Mastodon hosted on mastodon.social (https://brandsweets.com/colors/brands/mastodon-social). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 19 real palettes, including Kia's brand system and MongoDB's brand system put Blue beside #040d1b, as the accent. Seen in: Kia (https://brandsweets.com/colors/brands/kia-com), MongoDB (https://brandsweets.com/colors/brands/mongodb-com), Pfizer (https://brandsweets.com/colors/brands/pfizer-com), League of Legends (https://brandsweets.com/colors/brands/leagueoflegends-com). — https://brandsweets.com/colors/blue

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

- On white (#ffffff): 19.47:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.08:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #2e72e0 (4.6:1); AA: background → #7a7a7a (4.54:1); AAA: text → #6496e8 (7.07:1); AAA: background → #9c9c9c (7.09:1)

## Brands using this color

- **Audible** — text #010e19 (Δ 0.925) — https://brandsweets.com/colors/brands/audible-com
- **Hugging Face** — primary #0b0f19 (Δ 1.735) — https://brandsweets.com/colors/brands/huggingface-co

## Curated palettes containing it

- **Arcade** (neon, vivid, dark, bold) — #ff2e88, #00f0ff, #faff00, #0a0a14, #f5f5ff — Hot pink, cyan and acid yellow on near-black — cabinet-glow neon; the black surface is what makes the colours light up. — tool: https://brandsweets.com/palettes/new/ff2e88-00f0ff-faff00-0a0a14-f5f5ff — collection: https://brandsweets.com/palettes/neon

## 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/040d1b-9ca7c4-df624e-201f2d-e9f0f1?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: "#040d1b" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.