Multiply the number of days by 86,400 to calculate the equivalent in seconds; for months multiply by 2,592,000. For instance, three days equal 259,200 seconds, and two months equal 5,184,000 seconds.
Divide large number of seconds by 86,400 to find their equivalent in days and by 2,592,000 for their approximate equivalent in months. For example, 200,000 seconds equal approximately 2.31 days, and 3,000,000 seconds equal nearly 1.16 months. The value 2.31 for days stands for 2 1/3 days, or 2 days and 8 hours, and 1.16 months is 1 + (16/100) 30, or approximately 1 month and 5 days.
Add the exact number of days for the months in question. Because the number of days in a given month vary, multiplying the number of months by a specific number will not give accurate results.
Divide the number of days by 30.44 to convert them into months. For example, 120 days will be 120/30.44, or approximately 3.94 months. Again, this is not a fully accurate result, since the number of days within a month varies.