Bill Split Calculator
Split rent, utilities and shared bills between roommates or partners: equally, by income share, or by custom percentages, down to the exact cent.
Bill Split Calculator
How are you splitting?
Everyone in the table shares every bill. The method decides how big each share is.
Who is splitting
After-tax pay is the figure to use. Any consistent period works as long as everybody uses the same one, since only the ratio matters.
Two to eight people. A blank name falls back to "Person 1", "Person 2" and so on. Removing a row clears whatever was in it.
The bills
One row per shared bill. A blank amount is skipped entirely; a typed 0 counts as a real zero. Set "Paid by" only when one person already covered that bill out of pocket.
No bill amounts yet. Type what the rent, the utilities and the rest cost, and the split fills in as you go.
Results are paused until the custom percentages add up to exactly 100%.
Every share is worked out in whole cents, so the columns below add back to the exact bill total with no rounding drift.
Bill by bill
Read a row across for one bill, or a column down for one person. Scroll sideways on a phone.
Settle up
Everyone is square. No transfers needed.
Only bills with a payer set count here. Bills left on "Split pot" are still divided into what each person owes above.
Three ways to split the bills, and when each one fits
An equal split is the default here because it is the easiest agreement to remember and the hardest to argue about later. Nobody has to disclose a payslip, nobody has to recalculate when someone gets a raise, and the answer to "what do I owe" is the same every month. For housemates on broadly similar money, that is usually the end of the discussion.
Splitting by income is the answer when the paychecks are far apart and an even split is quietly squeezing one person. The same $900 of rent is a manageable line for someone taking home $5,000 a month and most of the month for someone taking home $2,200. A proportional split keeps the pressure roughly equal rather than the dollar amounts.
Custom percentages are the escape hatch for everything else: rent weighted by room size, a couple sharing one bedroom, the roommate who gets the parking space, or any house rule somebody negotiated on move-in day. Whichever you pick, the method matters less than writing it down before anyone signs the lease. Most roommate money arguments are really arguments about a rule that was never agreed out loud.
Splitting by income: the arithmetic behind a proportional share
Two people take home $4,000 and $6,000 a month and share $2,000 of bills. Combined take-home is $10,000, so the shares are 40% and 60%, which comes to $800 and $1,200. Each person hands over the same fraction of their pay, so the money left after the bills land is proportional too.
Only the ratio matters, which means it makes no difference whether both people enter monthly, biweekly, or annual figures, as long as they both use the same one. Use after-tax pay rather than salary. Two people on identical gross figures can take home very different amounts once health premiums, retirement contributions, and different withholding are out, and the gross number would tilt the split the wrong way. If one of the incomes moves around month to month, work out a dependable baseline first with the irregular income budget calculator and enter that figure.
Proportional shares almost never divide into whole cents, so this tool hands the leftover pennies to the largest fractional remainders and breaks ties by row order. Each bill still adds back to its exact total, which you can check in the grid. The FAQ below has the worked example.
Rent by room, utilities by household
To split rent by room size, total the private square footage each person gets: the bedroom plus any closet, private bathroom, or balcony only they use. Common areas stay out of the numerator because everybody shares them equally. Divide each person's private footage by the combined private footage and that is their percentage. If one bedroom has its own bathroom, the usual adjustment is to add about 100 square feet to that room's figure, which is how Splitwise's rent calculator handles an en-suite. Three bedrooms at 180, 140, and 120 square feet total 440, so the shares work out at 40.91%, 31.82%, and 27.27%. Enter those under Custom %.
Utilities are a different question, and the equal default is usually the right answer. Internet is one price whatever anyone streams. Water and the base load on an electric bill barely move with individual behaviour. Sub-metering each person sounds fairer on paper, but the bookkeeping is tedious and the totals get argued over anyway. Reserve the unequal treatment for a gap nobody can dispute, like the roommate running a window AC unit all summer. Shared streaming and music plans belong in the same pot: add them up with the subscription cost calculator, then enter the monthly total here as a single line.
Making the split stick after you close the calculator
The calculator settles this month. The failure mode is the third month, when someone forgets, someone else fronts the electric bill, and nobody remembers who is up. Two habits fix most of it. Fix a settle-up day right after the bills land, the same date every month, so squaring up is a routine rather than a confrontation. Then keep the recurring shares written down somewhere that reminds you instead of somewhere you have to remember to check.
The second habit is the one people skip. Your share of the rent and the utilities is a recurring bill like any other, and it belongs on the same calendar as the rest of your money. Budget44 logs it as a recurring monthly bill and shows the projected amount against what you have actually paid, on the device, with no account and no bank connection.
Frequently Asked Questions
Common questions about bill split calculator
How do you split bills fairly when roommates earn very different amounts?
Switch the method to "By income" and each person pays the same share of the bills as their share of household take-home pay. If one person brings in 60% of the money, they cover 60% of the rent and the utilities. The dollar amounts come out unequal on purpose. What a proportional split evens up is the money left over after the bills, not the bills themselves.
Should couples split bills 50/50 or by income?
50/50 is fine when the two incomes are close, and it is the simpler agreement to hold. Once the gap widens, the same dollar amount is a very different bite out of each paycheck, and the lower earner is left with less to save and less breathing room. A common middle path is proportional for the fixed household bills and even for discretionary spending. Run both methods here and compare the two sets of numbers before deciding. If one of the two incomes moves month to month, set a baseline first with the irregular income budget calculator.
How do you split rent by room size?
Add up the private square footage each person gets, which is the bedroom plus any closet, private bathroom, or balcony that only they use, and leave the kitchen and living room out. Divide each person's figure by the total, and that is their percentage. Enter those percentages in "Custom %". A private bathroom is usually counted as roughly 100 extra square feet of bedroom, which is the convention Splitwise's rent calculator uses.
How should roommates split internet, water, and electricity?
Internet almost always goes in as an even split, since the bandwidth is shared and nobody's streaming changes the bill. Water and the base load on an electric bill are usually the same story. Metering individual usage sounds fairer than it turns out to be in practice and tends to create more arguments than it settles. Save unequal treatment for the bills where the difference is large and obvious, such as one person running a window AC unit all summer. Shared streaming and music plans work the same way: total them with the subscription cost calculator, then enter the result here as one line.
What happens when a bill does not divide evenly?
Someone has to take the extra penny. Splitting $100.01 three ways gives $33.34, $33.34, and $33.33 rather than three shares of $33.3366 and a repeating tail. This calculator hands out the leftover cents to the largest fractional remainders first, breaking ties by row order, so the shares always add back to the exact bill total. Rotate which name sits in the first row if you want the odd penny to move around.
One person paid the whole bill. How do we settle up?
Set the "Paid by" dropdown on that bill row to whoever paid. The tool then compares what each person actually put in against what they owe and lists the transfers that square it up, using as few payments as it can. Bills you leave on "Split pot" are still divided and still count toward what each person owes, they just stay out of the settle-up arithmetic.
Is it fair to charge a couple sharing one room more than a single roommate?
Households land in different places on this one. The usual arguments are that two people in one room use more of the shared water, power, and kitchen, but they also take up less of the apartment's private space per head. A frequent compromise is to split rent by room and split utilities per person. Custom percentages let you write down whatever the house agrees to.
Are my numbers saved anywhere?
No. Everything runs in your browser, nothing is sent to a server, and nothing is stored. Reloading the page clears it.