Enter the rent, say how much of the flat is common area, and put in the size of each private room. The calculator splits the common portion equally and allocates the rest by room size.
Common areas are the living room, kitchen and shared bathrooms. That portion splits equally. The rest is allocated by private room size.
Why equal is wrong
Very few flats have equal rooms. One has the attached bathroom, one gets the balcony, one is the windowless box next to the kitchen that used to be a store room. Splitting the rent equally means the person in the box room subsidises everyone else, every month, for as long as the lease runs.
Nobody complains about this in month one. It surfaces in month eight as irritability about something unrelated.
How it works
The logic is straightforward once you separate the flat into two kinds of space.
- Common area is the living room, kitchen, balcony and shared bathrooms. Everyone uses it equally, so its share of the rent splits equally.
- Private area is each bedroom. Its share of the rent is allocated in proportion to room size.
The default of 40% for common area is a reasonable starting point for a typical Indian 2BHK or 3BHK. If your flat has a huge living room and small bedrooms, push it up. If it is mostly bedrooms with a corridor kitchen, push it down. The number does not need to be exact, it needs to be agreed.
Measuring the rooms
Pace it out or use a phone measuring app. Length times width per room is enough. You are producing relative sizes, not filing a survey, so being within a few square feet is fine.
Worth adjusting for
Square footage is a good baseline and it does not capture everything. Common adjustments people layer on top:
- Attached bathroom. Worth a real premium, often ₹1,500 to ₹3,000 a month depending on the city. Add it to that person's share before or after the area calculation, whichever is easier to explain.
- Balcony access from inside a room. Similar logic, smaller amount.
- A couple in one room. Two people using one room means more use of the common area, the water, the electricity. Many flats handle this by giving the couple's room a 1.5x weight rather than 2x, since they are still using one bedroom.
- The room with the AC. Do not put this in rent. Handle it in the electricity split, where it actually shows up.
Getting agreement
Do this before anyone moves in, ideally with everyone in the room. Once someone has unpacked into the big bedroom, renegotiating is a conversation with a loser in it.
Two things make the conversation easy. First, show the working. A number that comes out of a visible calculation is much easier to accept than a number someone proposes. Second, put the agreed split somewhere permanent. Write it into the group description in whatever app you use, so that in month nine there is a record instead of three different memories.
Agree it once
Once the numbers are agreed, use those exact shares every month and stop revisiting them. Everyone is looking at the same figures in the same place, so nobody has to reopen the maths or chase people from memory.
Splitify does this for free, along with the utilities, groceries and everything else. It also has no cap on how many expenses you can add in a day, which matters on the 1st when rent, electricity, internet, gas and the house help all land together. The full flatshare setup is covered in how to split rent and bills with flatmates.
Set rent up once and forget it
Recurring rent with your exact shares, posted every month. Free.
Common questions
How do you split rent fairly when bedrooms are different sizes?
Split the flat into common area and private area. The common portion, typically around 40% of the rent for an Indian 2BHK or 3BHK, splits equally because everyone uses the living room and kitchen. The remaining portion is allocated in proportion to each private room's square footage.
What percentage of rent should be assigned to common areas?
Around 40% works for most flats. Raise it if the living room and kitchen are large relative to the bedrooms, and lower it if the flat is mostly bedrooms. The exact figure matters less than everyone agreeing on it before anyone moves in.
How much extra should a room with an attached bathroom pay?
Commonly ₹1,500 to ₹3,000 a month depending on the city and the overall rent. It is a real convenience premium and pretending otherwise is what causes resentment later.
How should a couple sharing one room split rent?
Many flatshares weight the couple's room at around 1.5x rather than 2x. They occupy one bedroom but two people use the common area, the water and the electricity. Agreeing the multiplier up front avoids the argument entirely.
Is this rent calculator free?
Yes, no signup, and it runs entirely in your browser. Nothing you type is sent anywhere.