Most Vedic apps show the same Rahu Kaal for all of India, calculated from a generic IST formula. But Rahu Kaal is 1/8th of the actual daytime from today's sunrise at your location. Naperville is 10 hours 30 minutes behind India (IST). CosmosPandit uses precision astronomy (Jean Meeus, Astronomical Algorithms) to calculate the exact sunrise at Naperville's coordinates (41.785860°N, -88.147290°E), giving you the correct Rahu Kaal every day.
Naperville, Illinois, United States keeps America/Chicago time. Every Vedic daily timing here, the Panchang, Rahu Kaal, Choghadiya and Muhurat, is built from Naperville's own sunrise and sunset, not a single all-India (IST) table, so it is specific to Naperville and shifts a little each day. Naperville runs 10 hours 30 minutes behind India, so a timing copied from an Indian panchang is wrong here. The live panel on each page is recalculated daily for Naperville.
India uses a single timezone (IST, UTC+5:30) across 30° of longitude. But sunrise follows the sun, not the clock, every 1° of longitude, 4 minutes difference. Kolkata’s sunrise is 80 minutes earlier than Mumbai’s on the same IST day, so Rahu Kaal falls at genuinely different times in each city.
This Rahu Kaal page is just the start. The CosmosPandit app gives every Indian the full Vedic astrology toolkit, in their own language, with timings precise for their city:
The live panel above shows today's exact Rahu Kaal for Naperville, updated daily from local sunrise.
Traditionally yes for starting a journey or new work; travel already underway is unaffected.
Astronomically precise Rahu Kaal timings for 25 major Indian cities.