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Bill split calculator
Enter the bill and how many days each person was at home; the shares are worked out by person-days. If you would rather ignore the difference in days, pick an equal split.
The starting values are an example; replace them with your own.
How it works
A person's share = Bill × (their days ÷ total days). For example on a $240 bill, two people for 30 days and one for 15 days make 75 person-days; $3.20 per day, so $96, $96 and $48.
Days or equal?
If everyone was home all month, split equally. If someone moved in mid-month or was away for a long time, days are fairer. For usage differences (working from home, air conditioning) see our utility bill guide.
Frequently asked questions
How do roommates split a bill?
If everyone was home all month, split equally. If someone was only partly there, split by person-days.
What are person-days?
The total of the days each person spent at home. Divide the bill by it to get a per-day amount, then multiply by each person's days.
Should an absent roommate still pay?
For short absences the split usually stays equal. For long absences (a month or more), use a day-based calculation or a discount agreed beforehand.