Color
#3399ff
#3399ffrgb(51, 153, 255)hsl(210, 100%, 60%)oklch(0.676 0.176 252.3)Colors that go with #3399ff
Charcoal, Medium Sea Green and Tomato 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 #3399ff: softer than #000 and cool enough to feel like part of the same palette.
Medium Sea Green #3cb371
triadicshippedMedium Sea Green completes a triad with #3399ff — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Tomato #ff6347
split-complementshippedTomato is a split-complement of #3399ff: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Peru #cd853f
complementaryshippedPeru sits directly opposite #3399ff on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Amber #ffbf00
shippedAmber is paired with #3399ff in 8 real palettes, including Heatwave and Google's brand system, as the supporting colour.
Blue #0000ff
shipped12 real palettes, including Unity's brand system and Readymag's brand system put Blue beside #3399ff, as the supporting colour.
Dark Orange #ff8c00
shippedDark Orange shows up next to #3399ff 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 #3399ff: 6 real palettes, including Figma's brand system and Venmo's brand system.
Real palettes that use #3399ff
Tints & shades
Harmonies
Contrast
| #3399ff as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 2.94:1 | fail | fail | fail | |
Aaon black | 7.14:1 | pass | pass | pass | Passes AAA — no fix needed. |
Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3399ff as the background.
Brands using this color
Fonts for this mood
#3399ff reads as cool, vivid, technical. The font library is tagged with the same vocabulary:
Point 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.
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
›analyze #3399ff and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/3399ff-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