Kolkata

Asia • Kolkata

India

Current local time

09:44:28

Sunday, May 31, 2026

UTC offset

UTC+05:30

No daylight saving changes

Kolkata does not observe daylight saving time. Clocks stay on UTC+05:30 all year long.

Timezone details

Identifier
Abbreviation
—
Transitioned
May 31, 2021 at 06:30 AM
Featured city
Mumbai

Location

Latitude
22.53333
Longitude
88.36666
Country
India

India Standard Time (IST)

FAQs

India Standard Time (IST) unifies clocks across South Asia under a steady UTC+05:30 offset with India and Sri Lanka, meaning the sun hits the ground an unusual half-hour past the diagonal—ideal for coordinating bustling metros and monsoon schedules alike.

  • Why does India Standard Time sit at the oddball +05:30 offset?

    During the British era each major city kept solar time at its own meridian; in 1947 the newly independent India picked the +5:30 meridian near Allahabad as a midpoint between its eastern and western cities

  • Do any IST regions switch to daylight saving?

    Neither India nor Sri Lanka use daylight saving today, so IST stays fixed year-round and keeps scheduling simple across the subcontinent

  • Is India Standard Time the same as Sri Lankan Time?

    Yes—Sri Lanka Time was renamed from Colombo Mean Time to match India's +05:30 back in 2006 to align trade and broadcasting between the neighbors

  • Does the whole subcontinent really live on a single offset?

    Pretty much: from Gujarat's deserts to Assam's tea gardens clocks read the same, though eastern states use unofficial daylight-time habits and Nepal opts for its own +05:45

  • Is there an alternate abbreviation for India Standard Time?

    Informally people write IST, IT or simply +05:30 to avoid confusion with Irish Standard Time and Israel Standard Time which share the same letters

  • How does IST affect remote work with Western teams?

    Colombo lines up nine-and-a-half hours ahead of New York and ten-and-a-half ahead of London in winter, turning late-evening calls into next-morning replies for many collaborators

  • Why did India stay at +05:30 instead of picking a neater hour?

    Shifting the clocks would have meant the sun rising before 4:30 in the east and setting after 19:30 in the west, so officials kept the comfortable middle ground

  • What is the biggest practical upside of IST's half-hour offset?

    It lets eastern and western workdays overlap nicely without one end waking up too early, easing stock-market openings, cricket schedules and Bollywood release times

  • Is Nepal's unique +05:45 offset related to India Standard Time?

    Absolutely—in 1986 Kathmandu nudged 15 minutes ahead of IST to highlight national distinction and better align sunrise with the Himalayan valley of Kathmandu