Sleep Calculator

How to sleep in the Indian summer heat

When the night stays above 30°C, your body can't cool down enough to sleep deeply. Here's how to help it, with or without an AC.

6 min read. Updated 25 October 2026.

To fall asleep and stay in deep sleep, your core body temperature needs to drop by about a degree. In a hot room your body can't shed that heat, so you take longer to fall asleep, wake up more often, and get less deep and REM sleep. Indian summers, with nights that barely cool down in north India and heavy humidity on the coasts, are a serious sleep problem.

If you have an AC

  • 24 to 26°C is enough. Since 2020, the Bureau of Energy Efficiency has required new ACs in India to default to 24°C. With a fan running, that's cool enough for most people to sleep well, and cheaper than 18°C.
  • Use the fan with the AC. Moving air makes you feel two to three degrees cooler.
  • Cool the room before bed and use the sleep or timer mode so the temperature rises slightly towards morning, when your body is naturally coolest.
  • Don't blast cold air at your face. Point the vent away from the bed to avoid a blocked nose and sore throat.

Without an AC

  • Close windows and curtains by day, open them at night. Light-coloured curtains reflect heat, thick ones block it.
  • Cross-ventilation: a table fan near the window pushing air out, with another window open across the room, pulls cooler night air through.
  • Desert coolers work well in dry heat (Rajasthan, Delhi in May). In humid weather (Mumbai, Chennai, Kolkata, monsoon anywhere) they just add damp air.
  • Sleep low. Hot air rises. A mattress on the floor can be noticeably cooler, which is why many Indian families do exactly that in summer.
  • A damp cotton cloth on the feet or a cool towel on the neck lets evaporation do the work.

Bedding and clothes

  • Cotton or linen bedsheets. Skip synthetics and satin.
  • A thin cotton chadar instead of a blanket.
  • Loose cotton nightwear.
  • Foam mattresses trap heat. A cotton or khadi sheet over them, or a mat, helps.

Timing and habits

  • Shower 60 to 90 minutes before bed with lukewarm water, not ice cold. It draws heat to your skin, which then cools you as it evaporates.
  • Eat light at night. Digesting a heavy meal raises body heat. Curd rice, dal, khichdi and seasonal fruit are good summer dinners.
  • Drink water through the evening, but less in the last hour so you're not up at night.
  • Skip the late workout. Exercise in the morning or early evening instead.
  • Take a short afternoon nap on very hot days, when nights are short and broken anyway. Keep it to 20 minutes.

During heatwaves, older people, infants and people with heart or kidney conditions are at real risk even at night. Make sure they have the coolest room, plenty of fluids, and someone checking on them.