Turn your CTC into pay per hour: contracted, actually worked and every hour alive, before and after tax. See what a purchase costs in hours of your work.
Should I divide my pay by 365 days of 24 hours, or by 200 days of 8?
Both are right, for different questions. Over every hour alive your pay is a small number, about ₹121 an hour on the example above, and it tells you what your income comes to whether you work or not. Over the hours you are on duty it is far larger. The page shows both, because the gap between them is the point.
Why do my pay per working hour and per hour of every kind differ so much?
Because you work in a quarter of the hours you are alive. The same year of pay is spread over about 2,000 hours in one count and 8,760 in the other. Neither is a mistake. One is what an hour of your effort earns, the other is what an hour of your life brings in.
I am paid for 8 hours a day but I work 4, or 12. What do I earn an hour?
Enter the hours you are contracted for and the hours you really work. The page prices both. Work more than you are paid for and each hour you work earns less than the contracted rate. Work fewer and it earns more. The contracted rate is what your employer pays. The worked rate is what you get.
Is spending divided by the same hours as income?
No, and that is deliberate. Spending runs all day and all night: rent is due while you sleep. Income is earned only in the hours you work. So spending is divided by every hour in the year and income by the hours you work, and the page shows how many minutes of work one hour of your spending costs.
Is the rate I quote as a freelancer what I really earn an hour?
Almost never. The hours spent finding work, invoicing and chasing payment earn nothing, and neither do the weeks between projects or the invoices that are never paid. Counted over every hour you work, the rate you keep is a share of the one you quote, and the page says what share.