Ever noticed your Thai colleagues wearing yellow on Mondays, or wondered why government buildings display specific colours on certain days? You're witnessing one of Thailand's most charming traditions: the lucky colours of the weekday.
This living practice stems from ancient Hindu-Brahmin astrology woven into Thai Buddhist culture. Each day has an auspicious colour tied to celestial deities whose attributes shape the day's character. Understanding these colours offers expats insight into Thai cultural values and can help navigate social situations with greater awareness.
The tradition originates from the Navagraha system of Hindu astrology, where each day is ruled by a celestial deity, the Sun, Moon, or one of the five classical planets. Each deity has a body colour that becomes the day's auspicious hue. Thai armies historically marched under banners matching the day's colour for fortune, and royal ceremonies still honour monarchs with their birthday colours.
In Thai Buddhism, the Buddha's life events are linked to specific weekdays, and temples feature Buddha images for each day. Today, many Thais wear their birth-day colour for luck, particularly visible during royal celebrations.
Lucky colours of the week and their meanings
Sunday - Red: Ruled by Surya, the Sun god, Sunday's colour recalls dawn and sunset. Red represents energy and vitality. The Sunday Buddha image shows the "Meditating Buddha" in contemplative pose.
Monday - Yellow: The Moon god Chandra gives Monday its pale yellow, evoking moonlight and purity. This colour gained prominence through King Bhumibol Adulyadej, born on a Monday. Thais celebrated his birthday with yellow decorations, making yellow synonymous with respect for the beloved monarch. Coincidentally enough, the current King Vajiralongkorn was also born on a Monday, so people will still wear yellow during royal occasions.
Tuesday - Pink: Mars god Mangala traditionally appears red, but Thai tradition softens this to pink, representing courage under a gentler colour. King Rama V, born on a Tuesday, adopted pink as his royal colour. This extends to the university from his namesake, Chulalongkorn University, whose colour theme is pink in reverence to him.
Wednesday - Green: Mercury god Budha brings green, associated with growth and fortune. Wednesday is often considered Buddha's Day in Thai Buddhism, with significant events like receiving alms celebrated on this day.
Thursday - Orange: Jupiter's deity Brihaspati gives Thursday its bright golden-orange, suggesting warmth and knowledge. Orange reflects the wise, teacher-like nature of this day.
Friday - Light Blue: Venus deity Shukra is "cloud-coloured," standardised as sky-blue. Blue represents charm and compassion. This is the traditional colour for Friday-born royalty, including Queen Sirikit.
Saturday - Purple: Saturn god Shani's dark nature is rendered as purple in Thai custom (black being associated with mourning). Purple represents discipline and resilience. The Saturday Buddha shows protection by the naga serpent.
While not everyone dresses strictly by the calendar today, birthday colours remain significant. Many Thais wear their birth colour during important occasions for good luck, and it's common to see public servants in Thailand wearing specific lucky colours on corresponding days as a show of respect and tradition.
For you, understanding these colours can deepen cultural appreciation. If you're invited to a Thai celebration, asking about the guest of honour's birthday colour shows cultural awareness. Wearing that colour (or avoiding unlucky combinations) demonstrates respect. Government offices and schools sometimes encourage staff to wear day-appropriate colours, particularly on Mondays when yellow remains a visible tribute to the late King.
The tradition also offers insight into Thai values: the blending of Hindu astrology and Buddhist belief, the importance of auspicious timing, and the deep respect for royal tradition. Each colour carries its deity's attributes, such as red's energy, yellow's clarity, pink's courage, green's growth, orange's wisdom, blue's compassion, and purple's stability.
You don't need to restructure your wardrobe around this calendar, but knowing that your Thai friend's persistent yellow Monday shirts aren't just fashion, but a connection to centuries of tradition, adds a richer layer to understanding Thai culture. And if you happen to wear your own birthday colour for that important meeting?
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