A national panchang is wrong for most of India

Rahu Kaal is not a fixed time of day. It is the eighth part of the interval between sunrise and sunset, so it moves with both — and sunrise in Guwahati is 85 minutes earlier than in Rajkot. We computed it for every day of 2026 in 45 cities to find out how much that matters.

Where a Delhi panchang misleads most

Almanacs and newspaper panchang columns usually print one set of timings for the whole country, and in practice those are Delhi's. For a reader in Guwahati, Kolkata or Bhubaneswar that is not a rounding error — it is the difference between the inauspicious window being over and it not having started.

15 of 45 cities are off by half an hour or more at some point in the year. 32 are off by a quarter of an hour or more. The pattern is almost entirely east–west: India runs across roughly 29 degrees of longitude but keeps a single clock, so the sun reaches Gujarat nearly an hour and a half after it reaches Assam while both read the same time.

Why the error is not constant

If the only difference were longitude, every city's error would be a fixed offset and any almanac could simply publish a correction table. It does not work that way, for two reasons that compound:

• The day is a different length in each city. Rahu Kaal is one eighth of the daylight span, so a longer day makes a longer Rahu Kaal, not just a later one.
• That length changes through the year, by different amounts. Latitude decides how much. Srinagar swings 4h 34m between its shortest and longest day; Kochi, near the equator, only 1h 10m — a 3.9× difference.

So the gap between a national panchang and a local one widens and narrows with the season, and it does so at a different rate in Srinagar than in Kochi. That is why we compute per city per day rather than publishing an offset.

Day length across 2026

The five widest swings and the three narrowest. Latitude explains almost all of it: the further from the equator, the more the year stretches and compresses the day.

All 45 cities

Errors are against Delhi for the same IST date, in minutes. Day lengths are the shortest and longest of 2026.

Method, and the raw data

Sunrise and sunset come from the Swiss Ephemeris using the Lahiri ayanamsa — the same engine professional Vedic astrology software uses — solved independently for each city's coordinates on each of the 365 days of 2026. Rahu Kaal follows the standard construction: the daylight span divided into eight parts, with the inauspicious part set by the weekday. All times are IST.

Nothing here is estimated or interpolated, and there is no model or forecast involved — given a date and a pair of coordinates the answer is deterministic. Anyone can reproduce it.

• Every row we computed: daylight-2026.csv — 16,425 rows (one per city per day) with sunrise, sunset, day length and the Rahu Kaal window. 1.2 MB, CC BY 4.0.
• Or just the per-city summary: daylight-2026.json — the 45 rows behind the table above. 11 KB.
• If you use either, please link back to this page. That is the whole licence in practice.
• Or compute it yourself: the free API serves the same panchang for any coordinates, no key required.
• Or just read today's: panchang for 45 cities, updated every morning.