Heatwave
Open in tool →Blaze orange and hot yellow with one cold blue — the high-noon palette; use the blue where the eye needs to rest.
Color
#258cf4
#258cf4
hex
#258cf4rgb
rgb(37, 140, 244)hsl
hsl(210, 90%, 55%)oklch
oklch(0.637 0.18 253.2)Closest name: dodgerblue (#1e90ff)Relative luminance 0.2568
Colors that go with #258cf4
Charcoal, Crimson 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 #258cf4: softer than #000 and cool enough to feel like part of the same palette.
Crimson #dc143c
triadicshippedCrimson completes a triad with #258cf4 — 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 #258cf4 in 11 real palettes, including Heatwave and Google's brand system, as the supporting colour.
Blue #0000ff
shipped11 real palettes, including Unity's brand system and Readymag's brand system put Blue beside #258cf4, as the supporting colour.
Cobalt Blue #0047ab
shippedDesigners have shipped Cobalt Blue with #258cf4: 10 real palettes, including Carrefour's brand system and Blue Mono, as the accent.
Dark Orange #ff8c00
shippedDark Orange shows up next to #258cf4 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 #258cf4: 10 real palettes, including Venmo's brand system and Patreon's brand system, as the supporting colour.
Denim #1560bd
shippedDesigners have shipped Denim with #258cf4: 19 real palettes, including Venmo's brand system and Coursera's brand system, as the accent.
Real palettes that use #258cf4
Tints & shades
Harmonies
Contrast
| #258cf4 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 3.42:1 | fail | pass | fail | |
Aaon black | 6.14:1 | 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 #258cf4 as the background.
Brands using this color
Palettes built around it
Fonts for this mood
#258cf4 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:
mcpConnect your agent — build around #258cf4
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 #258cf4 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/258cf4-9cabc4-df514e-1f202d-e9f1f1?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