Brick Underground’s Gross Rent Calculator: How to figure out the rent you’ll actually owe each month

New York City is an expensive—and tricky—place to rent. If you’re on a budget (like most people) you need to know exactly how much you are going to shell out every month. But sometimes the rent you see advertised for an apartment that you have your heart set on is not the rent you end up paying—ouch!

That’s because when landlords have vacant apartments they may offer concessions in order to fill them quickly. Some NYC landlords offer a free month or two when the market is soft or the apartment is difficult to rent (like when it’s on the ground floor), which is a good thing for you as a renter.

[Editor’s note: A previous version of this article ran in July 2024. We are presenting it again in case you missed it.]

Here’s where it gets tricky: Landlords use that concession to advertise the apartment at a lower, net effective rent. Essentially this means they take the discount and shave a little off each month, so when they advertise, it looks less expensive than it actually is. So an apartment that’s advertised with a net effective rent of $3,300 with one month free on a 12-month lease may actually have a lease that says it is $3,600 a month.

Even if you set your search parameters to fit your maximum budget of $3,300, the results you get—and what you may unwittingly fall in love with—may actually be that more expensive apartment.

To be clear, it’s not a scam to list an apartment by its net effective rent, but it can feel like something akin to a bait and switch. If you’re not paying attention, or you lack the patience or math skills required to calculate the actual rent, you will be in for a nasty surprise.

It’s also important to consider what can happen when your lease is up for renewal: If the landlord decides to raise the rent, it will be based on the higher, actual rent, called the gross rent, so the increase will feel pretty steep. 

Fortunately, it takes only a couple of seconds to figure out the real rent using Brick Underground’s Gross Rent Calculator, below. Bookmark this page to keep the calculator handy as you navigate and compare listings that advertise net effective rents versus the amount you’ll need to fork over each month. 

Brick Underground’s

Gross Rent Calculator

What’s this?

Some New York City landlords offer a free month (or more) at the
beginning or end of a lease. The advertised rent is the net
effective rent.  The net effective rent is less than the
amount you will actually have to pay — known as your gross
rent — during your non-free months.

Brick Underground’s Gross Rent Calculator enables you to
easily calculate your gross rent, make quick apples-to-apples
comparisons between apartments and avoid expensive surprises. All
you’ll need to figure out your gross rent is 1) the net effective
rent, 2) the length of your lease, and 3) how many free months your
landlord is offering.  [Hint: Bookmark this page for easy
reference!]

To learn more about net effective versus gross rents, read What
does ‘net effective rent’ mean?.

Net Monthly Advertised Rent

Per Month

Continue

Length of Lease

Months

Number of Free Months

Months

If the landlord is offering partial months free, enter it
with a decimal point. For example, 6 weeks free rent should
be entered as 1.5 months.

Calculate

Your Real Monthly Rent:

Per Month

Find Rentals Offering Concessions »