Warm and cool colors
Oranges feel warm and blues cool. Green and violet are up for debate. Physics runs the other way.
- Reliably warm
- Red, orange, yellow
- Reliably cool
- Blue
- Contested
- Green and violet: warm, cool or neither
- Kelvin scale
- Higher number = bluer light
Painters sort colors by temperature. Reds, oranges and yellows reliably feel warm, like fire and sun; blues reliably feel cool, like water and shade. Green and violet are contested: each sits between a warm and a cool, so whether one reads warm, cool or neither depends on which way it leans and what's beside it. Goethe framed the split in his Theory of Colours as a polarity: a lively 'plus' side of yellow and orange and a restless 'minus' side of blue.
Temperature is relative. Crimson gets called a cool red beside vermilion, though it's more precise to say crimson is purpler and vermilion oranger. A teal can look warm next to an icy blue, and whites and greys lean too: put a creamy white beside a bluish one and both leans jump out. In a lab study of 'color emotion' with British and Chinese observers, warmth peaked near red-orange and coolness at the opposite hue, a greenish blue, and stronger colors felt warmer or cooler than dull ones.
Physics runs the other way. Heat a piece of iron and it glows red, then yellow, then bluish white as it gets hotter. Light bulbs are rated on this scale in kelvin, so a 'warm' 2,700 K bulb is rated lower than 'cool' 6,500 K daylight. Our words follow feelings about fire and ice, not thermodynamics.
Does a warm-colored room feel warmer? This 'hue-heat' idea has been tested for decades with mixed results. In paintings, though, temperature does real work. Outdoors, sunlit surfaces look warm while shadows, lit by blue sky instead of sun, look cool, which is why the Impressionists painted violet shadows. Monet's Impression, Sunrise hangs one orange sun in a cool blue-grey harbor.
Swatches
- Vermilion · warm, oranger red
- Crimson · cooler, purpler red
- Blue · reliably cool
- Green · contested
- Violet-purple · contested
- Ecru · warm white
- White · cooler white
- 2,700 K bulb · 'warm' light
- 6,500 K daylight · 'cool' light
Colors
Sources
- Goethe, J. W. von (1810). Zur Farbenlehre; trans. C. L. Eastlake (1840), Theory of Colours, Part VI.
- Ou, L.-C., Luo, M. R., Woodcock, A. & Wright, A. (2004). A study of colour emotion and colour preference. Part I: Colour emotions for single colours. Color Research & Application 29(3): 232–240.
- Gage, J. (1993). Colour and Culture. Thames & Hudson.
- Battistel, L., Zandonella Callegher, R., Zampini, M. & Parin, R. (2024). Investigating the validity of the hue-heat effect on thermal sensitivity. Scientific Reports 14: 21413.
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