Retro Pop
Open in tool →Fifties-diner red and steel blue with a peach — nostalgic pop that still passes contrast.
Color
#377ea4
#377ea4
hex
#377ea4rgb
rgb(55, 126, 164)hsl
hsl(201, 50%, 43%)oklch
oklch(0.565 0.092 235.1)Closest name: Cry Me a River (#427898)Relative luminance 0.1841
Colors that go with #377ea4
Charcoal, Crimson and Royal Blue 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 #377ea4: softer than #000 and cool enough to feel like part of the same palette.
Crimson #dc143c
split-complementshippedCrimson is a split-complement of #377ea4: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Royal Blue #4169e1
analogousshippedRoyal Blue is #377ea4's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Sienna #a0522d
complementaryshippedSienna sits directly opposite #377ea4 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 #377ea4 in 8 real palettes, including Beach Hut and Wired's brand system, as the supporting colour.
Blue #0000ff
shipped5 real palettes, including Activision's brand system and Pixar's brand system put Blue beside #377ea4, as the accent.
Cobalt Blue #0047ab
shippedDesigners have shipped Cobalt Blue with #377ea4: 8 real palettes, including Glacier and Hershey's's brand system, as the accent.
Copper #b87333
shippedDesigners have shipped Copper with #377ea4: 5 real palettes, including Riverbed and Notion's brand system, as the accent.
Real palettes that use #377ea4
Tints & shades
Harmonies
Contrast
| #377ea4 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 4.48:1 | fail | pass | fail | |
Aaon black | 4.68:1 | 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 #377ea4 as the background.
Brands using this color
No public brand in the corpus uses this exact color yet. Extract a brand to add one.
Palettes built around it
Fonts for this mood
#377ea4 reads as cool, modern. The font library is tagged with the same vocabulary:
mcpConnect your agent — build around #377ea4
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 #377ea4 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/377ea4-9cb1c4-df4e62-1f222d-e9f1f0?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