Scarlet

Red raises heart rate and energy levels and is strongly linked to passion, excitement and urgency. It grabs attention faster than any other hue, which is why it powers sale signs, alerts and appetite-driven food branding.

Red is the go-to for calls-to-action, error states, warnings, sale badges and romantic or festive designs. Brighter reds suit e-commerce and entertainment, while deeper, muted reds feel luxurious and are common in wine, heritage and editorial branding.

Red ochre was among the first pigments used in prehistoric cave art more than 40,000 years ago. Later vivid reds came from cinnabar, kermes insects and madder root, and the modern era replaced them with stable synthetic pigments such as cadmium and quinacridone reds.

Red carries rich, sometimes opposite meanings: love and luck in China, courage and sacrifice in heraldry, and danger or stop in Western signaling. It is universally treated as a high-priority, high-emotion color.

Choose red when you want to command attention, create urgency or express passion, strength and confidence. It is ideal for brands and interfaces that need a bold, warm and energetic accent.

Against white, #FF2400 has a 3.8:1 contrast ratio; against black it is 5.5:1. Black text on #FF2400 meets WCAG AA for normal text.

Roughly 180° across the wheel from #FF2400 (hue 8°) sits #00ddff, held together by the #f99586 tint and the neutrals #f4f4f5 and #18181b.

#FF2400 with its two closest neighbours, #ff005d and #ffa200, for a 100%-saturation run that stays inside one family; #f99586 and #801100 add depth without breaking it.

#FF2400 plus #00ff22 and #2200ff, a triangle that sits 120° apart at every corner, with #f4f4f5 and #18181b doing the quiet work underneath.

One hue at 5 lightness steps: #ffedeb through #1f0400, starting from #FF2400 at 50% lightness.