# Pro-Rata Share Calculator | Free CRE Tool

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# Operating expense clarity

Calculate tenant proportionate share of operating expenses across gross, modified gross, and triple-net lease structures.

GrossModified grossTriple-netBase yearGross-up

Runs locally · Nothing is saved or sent to a server

## Every lease negotiation involves OpEx calculations

Operating expense pass-throughs are among the most negotiated provisions in commercial leases. Clear, accurate calculations benefit both sides of the table.

1.  ### Every deal involves OpEx
    
    Operating expense calculations are part of virtually every commercial lease negotiation. Getting them wrong starts the relationship on the wrong foot.
    
2.  ### Structures vary widely
    
    Gross, modified gross, triple-net, base year, expense stop. Each structure calculates tenant responsibility differently.
    
3.  ### Both sides need the numbers
    
    Landlords and tenants both model OpEx exposure. Currently done in ad-hoc spreadsheets with inconsistent assumptions.
    

## What you can calculate

1.  ### Gross, modified gross & triple-net
    
    Calculate pro-rata share under any lease structure, from full-service gross to absolute triple-net.
    
2.  ### Base year & expense stop
    
    Model tenant exposure with base year stops, expense stops, and year-over-year escalation caps.
    
3.  ### CAM, insurance & taxes
    
    Break down operating expenses into individual components: common area maintenance, insurance, real estate taxes.
    
4.  ### Year-over-year caps
    
    Limit tenant exposure with controllable expense caps that restrict year-over-year increases to a defined percentage.
    
5.  ### Building-wide calculations
    
    Calculate pro-rata share based on rentable square footage as a proportion of total building area.
    
6.  ### Gross-up provisions
    
    Adjust operating expenses to reflect full occupancy, protecting landlords from vacancy-driven cost spikes.
    

At your service

## OpEx calculations, built into the lease

LeasePilot generates operating expense provisions with accurate pro-rata calculations, no separate modeling needed.

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