Studio Grey
Open in tool →A pure greyscale with a single electric blue — the portfolio palette that makes work look considered.
Color
#398cf9
#398cf9
hex
#398cf9rgb
rgb(57, 140, 249)hsl
hsl(214, 94%, 60%)oklch
oklch(0.645 0.181 256.7)Closest name: dodgerblue (#1e90ff)Relative luminance 0.2647
Colors that go with #398cf9
Charcoal, Red and Amber lead the list. Each partner is a real named colour with the reason it works — a wheel relationship, a neutral that carries it, or a pairing lifted from a palette or brand system that actually shipped — and every pair opens in the palette tool.
Charcoal #36454f
neutralshippedCharcoal is the text near-black for #398cf9: softer than #000 and cool enough to feel like part of the same palette.
Red #ff0000
triadicshippedRed completes a triad with #398cf9 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Amber #ffbf00
shippedAmber is paired with #398cf9 in 11 real palettes, including Google's brand system and Heatwave, as the accent.
Blue #0000ff
shipped11 real palettes, including Unity's brand system and Readymag's brand system put Blue beside #398cf9, as the supporting colour.
Cobalt Blue #0047ab
shippedDesigners have shipped Cobalt Blue with #398cf9: 9 real palettes, including Blue Mono and Carrefour's brand system, as the lead colour.
Crimson #dc143c
shippedCrimson is paired with #398cf9 in 8 real palettes, including Behance's brand system and NASCAR's brand system, as the accent.
Dark Orange #ff8c00
shippedDark Orange shows up next to #398cf9 in 4 real palettes, including Playground and Elastic's brand system, as the lead colour.
Deep Sky Blue #00bfff
shippedDesigners have shipped Deep Sky Blue with #398cf9: 10 real palettes, including Venmo's brand system and Patreon's brand system, as the supporting colour.
Real palettes that use #398cf9
Tints & shades
Harmonies
Contrast
| #398cf9 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 3.34:1 | fail | pass | fail | |
Aaon black | 6.29:1 | pass | pass | fail |
|
Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #398cf9 as the background.
Brands using this color
Palettes built around it
Fonts for this mood
#398cf9 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:
mcpConnect your agent — build around #398cf9
live endpointPoint any MCP client at the shared colors endpoint and your agent gets the same engine as this page — direct_palette, edit_direction, check_palette, check_contrast — read-only, no key. Every direction it proposes comes with a /colors/d/… link: open it, lock what you like, paste the link back, and the agent edits rather than re-rolls.
endpoint
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt
›analyze #398cf9 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/398cf9-9ca9c4-df5a4e-1f1f2d-e9f0f1?lock=0&style=vibrantWant the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.
Machine-readable: color.md