Rent Per Sq Ft Calculator
A $2,000 apartment sounds expensive until you learn it is twice the size of a $1,500 unit. Rent per square foot is the fair way to compare spaces of different sizes, and this calculator works it four ways: rent from size and rate, rate from rent and size, a side-by-side comparison of up to three properties, and a market check with a plain verdict. Pick the property type first, because residential space quotes by the month and commercial space quotes by the year, and the result leads with the convention your market actually uses.
Industry convention: homes rent by the month, commercial space by the square foot per year.
Quick Answer
A $2,400 apartment at 1,200 sq ft costs $2.00 per sq ft per month ($24.00 per year), with annual rent of $28,800. Against a $2.20 market rate, the Market check mode calls that 9.1% below market: good value. A 3,000 sq ft office at $3.00 per sq ft per month quotes as $36.00 per sq ft per year, $9,000 a month. Enter your own rent and size above for the same readouts.
Key takeaways
- Rent per sq ft = monthly rent ÷ square footage. It is the only honest way to compare two spaces of different sizes.
- Residential quotes lead monthly, commercial quotes lead yearly. The tool shows both rates every time and swaps the headline to match the property type.
- The cheaper total rent is often the worse deal: $1,500 for 600 sq ft ($2.50) loses to $1,800 for 900 sq ft ($2.00) in Compare 3 mode.
- Compare on one area basis only. A rate quoted on rentable area is not comparable to one quoted on usable area; the section below explains the gap.
How to use the four modes
Each mode answers a different question, and the property type selector applies to all four. Set the property type first, then pick the tab that matches what you know.
- Rent from size: you know the area and the monthly rate, and want the rent. The pre-filled 1,200 sq ft at $2.00 returns a monthly rent of $2,400.00.
- Rate from rent: you know the rent and the area, and want the rate. The pre-filled $2,400 on 1,200 sq ft returns $2.00 per sq ft per month ($24.00/yr).
- Compare 3: enter rent and size for two or three listings. The tool prints each rate and names the lowest one best value.
- Market check: enter one listing plus a market rate. The tool adds a verdict: overpriced, fair, good value or excellent value.
Results stay hidden until you click Calculate, and switching tabs hides the previous result. Invalid entries are rejected in plain language: a blank size gets "Enter the square footage.", a zero or negative rent gets "Monthly rent must be above zero.", and Compare 3 with fewer than two complete properties gets "Enter at least 2 properties with rent and square footage." Reset restores the worked-example values in every panel.
The formulas behind each mode
Every mode is one division or one multiplication, run in whichever direction you need. There is no hidden adjustment, no rounding of the rate before it is displayed beyond two decimals, and no fees added.
Monthly Rent = Square Footage × Rate per Sq Ft (per month)
Annual Rent = Monthly Rent × 12 | Annual Rate = Monthly Rate × 12
Market difference % = (Property Rate − Market Rate) ÷ Market Rate × 100
One input convention matters: the rate fields always take the monthly rate, even in commercial mode. A broker quoting $36.00 per sq ft per year is quoting $3.00 per month, so enter 3. The tool then leads the result with the yearly figure for commercial property, which is the number the listing used. Both figures are printed either way, so nothing is lost in translation.
Worked examples: apartment, comparison, office
Three runs cover the situations readers actually hit. Every number below is a real run of the calculator above, so you can retype any of them and get the same output.
| Run | Inputs | Tool output |
|---|---|---|
| Apartment rate | $2,400/mo, 1,200 sq ft, residential | $2.00 per sq ft per month ($24.00/yr); annual rent $28,800.00 |
| Comparison | A $1,500 / 600 sq ft; B $1,800 / 900 sq ft | Best value: Property B at $2.00; A works out to $2.50 |
| Office lease | 3,000 sq ft at $3.00/mo, commercial | Monthly rent $9,000.00; headline $36.00 per sq ft per year; annual $108,000.00 |
| Market check | $3,000/mo, 1,000 sq ft, market $2.50 | $3.00 per sq ft; 20.0% above market: overpriced |
The comparison row is the one that changes minds. Apartment A is $300 a month cheaper and still the worse buy, because you pay $2.50 for each square foot instead of $2.00. Total rent tells you what leaves your account; the rate tells you what you got for it.
Rentable vs usable square feet: the basis trap
A rate is only meaningful next to the area it was divided by, and commercial listings use two different areas. Usable square footage is the space you actually occupy. Rentable square footage adds your share of the lobbies, hallways and restrooms, under measurement standards such as the ANSI/BOMA Z65.1 method published by the Building Owners and Managers Association.
That gap is why a 2,000 sq ft office can bill like a 2,300 sq ft one. If you are comparing commercial quotes, run them through the rentable square footage calculator first so every rate sits on the same rentable basis, and keep the metric straight when a listing switches to square meters with the price per square meter calculator. Mixing bases mid-comparison is the single most common way this math misleads, and no calculator can rescue a comparison built on two different denominators.
Reading the market check verdicts
The verdict compares your property rate with the market rate you entered, as a percentage difference. The bands are fixed, and the table below states them exactly as the tool applies them, including two boundary behaviors worth knowing.
| Difference vs market | Verdict | How to read it |
|---|---|---|
| More than 10% above | overpriced | Negotiate, or walk. At $3.00 against a $2.50 market the gap is 20.0%. |
| Above market, up to exactly 10% above | fair | A premium for condition or location can justify this band. |
| At market, down to just under 10% below | good value | At or under the going rate. A property priced exactly at market lands here too. |
| 10% below or more | excellent value | Check the catch: condition, lease length, or a size measured on a different basis. |
Two boundary quirks, stated honestly. Exactly 10% above market still reads "fair" (the overpriced band starts above 10%), while exactly 10% below market already reads "excellent value" rather than "good value". And a property priced exactly at the market rate prints "0.0% below market: good value." The verdict is only as good as the market rate behind it, so source that number from real comparable listings or published fair market rent data, not from the listing you are checking. Once the rate looks right, the separate question is whether the total rent fits your income, which the 40x rent rule calculator answers, and whether renting beats buying at all, which the rent or buy calculator works through.
What competing calculators miss
Most rent per square foot tools do the single division and stop. Checking the top results for this keyword shows the same gaps repeating:
- One direction only. Calculator City style tools divide rent by area and finish. Landlords and brokers just as often start from a rate and need the rent, which is a separate mode here.
- No quoting-convention switch. Commercial guides (SquareFoot, Cauble Group, Atrium) explain carefully that commercial rent is quoted per year, then their tools still headline the monthly figure. This tool swaps the headline rate with the property type, the way the listing itself reads.
- No head-to-head comparison. Guide pages walk through an A-versus-B example in prose, but the reader still runs two separate calculations and compares by hand. Compare 3 mode does it in one run and names the winner.
- No market verdict. Rivals report a rate and leave "is that good?" unanswered. The market check turns the rate into a position against a market number, with the bands published on the page.
- Unit conversion dressed up as a feature. Square-meter conversion is genuinely useful for some readers, but it does not fix a comparison built on mixed usable and rentable areas. This page spends its space on the basis trap instead.
Frequently asked questions
Divide the monthly rent by the square footage. A $2,400 apartment at 1,200 sq ft is 2,400 ÷ 1,200 = $2.00 per sq ft per month, or $24.00 per sq ft per year. The Rate from rent mode runs exactly this division.
Residential rent is quoted per square foot per month; commercial space (office, retail, industrial) is quoted per square foot per year, except in parts of California where commercial also quotes monthly. This calculator always shows both rates and leads with the one your property type uses.
Multiply the square footage by the monthly rate. In Rent from size mode, 3,000 sq ft at $3.00 per sq ft per month gives a monthly rent of $9,000.00. If your rate is quoted yearly, divide it by 12 first: a $36.00 yearly rate is $3.00 a month.
There is no universal good number, because rates track the local market. Use Market check mode: more than 10% above the local market rate reads as overpriced, at or just below market reads as good value, and 10% or more below market reads as excellent value.
It computes rent ÷ square footage for each complete property and names the lowest rate best value, even if that property has the highest total rent. On an exact tie, the property listed first wins: A before B before C. Properties left blank, or with rent but no square footage, are left out.
Use whichever basis the rate was quoted on, and use the same basis for every property in a comparison. Usable area is your private space; rentable area adds your share of common areas, so a rate on rentable area looks lower for the same space. Mixing the two bases in one comparison produces a wrong winner.
No. The property type only changes which rate leads the result: monthly for residential, yearly for commercial. The underlying numbers are identical either way, and both the monthly and yearly rates are always printed, so you can cross-check a listing quoted the other way.
Include them in every property or in none. In commercial triple-net (NNN) leases, taxes, insurance and common area maintenance (CAM) sit on top of base rent, so a low headline rate can hide a high true cost. For an apples-to-apples rate, add the same charges to each listing before you compare.
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References
- U.S. Department of Housing and Urban Development, HUD User. Fair Market Rents Documentation and Datasets (published fair market rents by area and unit size, the market-rate source suggested for the Market check mode). Accessed October 24, 2026.
- U.S. Bureau of Labor Statistics. Consumer Price Index, Table 1 (includes rent of primary residence) (official rent price index used to track how asking rates move over time). Accessed October 24, 2026.
- Building Owners and Managers Association (BOMA) International. Floor Measurement Standards, ANSI/BOMA Z65.1 (the rentable versus usable area measurement method behind commercial square footage figures). Accessed October 24, 2026.
- U.S. Census Bureau. Housing Vacancies and Homeownership (Rental Vacancy Survey) (quarterly rental vacancy and rent data by region). Accessed October 24, 2026.
- U.S. Energy Information Administration. Commercial Buildings Energy Consumption Survey (CBECS) (official data on commercial building size and floorspace in the United States). Accessed October 24, 2026.
- National Association of Realtors. Commercial Real Estate Market Insights (commercial leasing market reports covering asking rents by property type). Accessed October 24, 2026.