Answer

No, generally not by 4.

For porsi calculation in Jain practice, the usual method is to take the time between sunrise and sunset and divide it into 8 equal parts. So:

• Sunset − Sunrise = total daytime
• Total daytime ÷ 8 = 1 porsi

If you divide by 4, that gives you 2 porsis, not 1.

Explanation

In traditional Jain time calculation, porsi is usually understood as a fraction of the day based on the interval from sunrise to sunset.

So if daylight is 12 hours:

• 12 ÷ 8 = 1.5 hours per porsi

If daylight is 10 hours:

• 10 ÷ 8 = 1.25 hours per porsi

This is why the length of a porsi changes with the season.

Spiritual Understanding

Jain observances often follow the natural rhythm of the sun. That is why porsi is measured from sunrise to sunset, not by a fixed clock length.

This helps maintain:

• discipline in daily practice
• alignment with traditional Jain observances
• proper timing for vows, meals, and spiritual routines

Takeaway

To calculate porsi, divide the sunrise-to-sunset duration by 8, not 4. If you want, I can also explain sardha porsi, adha porsi, and purimaddha porsi in a simple table.