# #309ef8

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

## Values

- Hex: `#309ef8`
- RGB: rgb(48, 158, 248)
- HSL: hsl(207, 93%, 58%)
- OKLCH: oklch(0.682 0.164 248.3)
- Relative luminance: 0.3186
- Nearest named color: Fresh Blue of Bel Air (#069af3, Δ 1.932) — https://brandsweets.com/colors/fresh-blue-of-bel-air
- Moods: cool, vivid, technical, modern
- Page: https://brandsweets.com/colors/309ef8

## Tints & shades

- Tints (toward white): #44a7f8, #58b0f9, #6bbafa, #7fc3fa, #93ccfb, #a6d5fc, #badffd, #cee8fd, #e1f1fe, #f5faff
- Shades (toward black): #1892f7, #0883e7, #0775cf, #0664b1, #065699, #054880, #043862, #032a4a, #02192c, #010b14

## Harmonies

- Complementary: #f88a30
- Analogous: #30f8ee, #303af8
- Triadic: #f8309e, #9ef830
- Split-complementary: #f8303a, #f8ee30
- Tetradic: #ee30f8, #f88a30, #3af830

## Colors that go with #309ef8

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 #309ef8: softer than #000 and cool enough to feel like part of the same palette. Seen in: Blizzard (https://brandsweets.com/colors/brands/blizzard-com), Lamborghini (https://brandsweets.com/colors/brands/lamborghini-com), Lido (https://brandsweets.com/palettes/vivid#lido), Lagoon (https://brandsweets.com/palettes/vivid#lagoon). — https://brandsweets.com/colors/charcoal
- **Medium Sea Green** #3cb371 [harmony, pool: triadic] — Medium Sea Green completes a triad with #309ef8 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Terminal (https://brandsweets.com/palettes/technical#terminal), Unity (https://brandsweets.com/colors/brands/unity-com), Olympics (https://brandsweets.com/colors/brands/olympics-com), Spotify (https://brandsweets.com/colors/brands/spotify). — https://brandsweets.com/colors/mediumseagreen
- **Tomato** #ff6347 [harmony, pool: split] — Tomato is a split-complement of #309ef8: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Replit (https://brandsweets.com/colors/brands/replit), Lido (https://brandsweets.com/palettes/vivid#lido), Substack (https://brandsweets.com/colors/brands/substack-com), Abstract (https://brandsweets.com/colors/brands/abstract-com). — https://brandsweets.com/colors/tomato
- **Peru** #cd853f [harmony, pool: complementary] — Peru sits directly opposite #309ef8 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Guinness (https://brandsweets.com/colors/brands/guinness-com). — https://brandsweets.com/colors/peru
- **Amber** #ffbf00 [pool] — Amber is paired with #309ef8 in 7 real palettes, including Heatwave and NBA's brand system, as the supporting colour. Seen in: Heatwave (https://brandsweets.com/palettes/warm#heatwave), NBA (https://brandsweets.com/colors/brands/nba-com), Salesforce (https://brandsweets.com/colors/brands/salesforce-com), Google (https://brandsweets.com/colors/brands/google-com). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 9 real palettes, including Unity's brand system and Readymag's brand system put Blue beside #309ef8, as the supporting colour. Seen in: Unity (https://brandsweets.com/colors/brands/unity-com), Readymag (https://brandsweets.com/colors/brands/readymag-com), Qualcomm (https://brandsweets.com/colors/brands/qualcomm-com), Warp (https://brandsweets.com/colors/brands/warp-dev). — https://brandsweets.com/colors/blue
- **Dark Orange** #ff8c00 [pool] — Dark Orange shows up next to #309ef8 in 4 real palettes, including Elastic's brand system and Learning App, as the lead colour. Seen in: Elastic (https://brandsweets.com/colors/brands/elastic-co), Learning App (https://brandsweets.com/palettes/playful#learning-app), Playground (https://brandsweets.com/palettes/bold#playground), Ahrefs (https://brandsweets.com/colors/brands/ahrefs-com). — https://brandsweets.com/colors/darkorange
- **Denim** #1560bd [pool] — Designers have shipped Denim with #309ef8: 8 real palettes, including Apple's brand system and Venmo's brand system, as the accent. Seen in: Apple (https://brandsweets.com/colors/brands/apple-com), Venmo (https://brandsweets.com/colors/brands/venmo-com), Gopro (https://brandsweets.com/colors/brands/gopro-com), Coursera (https://brandsweets.com/colors/brands/coursera-org). — https://brandsweets.com/colors/denim

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

- On white (#ffffff): 2.85:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #0878d4 (4.52:1); AA: background → #303030 (4.63:1); AAA: text → #06599d (7.18:1); AAA: background → #080808 (7.03:1)
- On black (#000000): 7.37:1 — AA pass, AA-large pass, AAA pass

## Brands using this color

- **JetBrains** — secondary #18a3fa (Δ 1.392) — https://brandsweets.com/colors/brands/jetbrains-com
- **AMD** — secondary #2899ff (Δ 1.912) — https://brandsweets.com/colors/brands/amd-com

## 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/309ef8-9cadc4-df4e53-1f212d-e9f1f1?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: "#309ef8" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.