Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
Site EUI
57.3
Total annual energy
5,729,600
ENERGY STAR median for type
67
vs. median (positive = worse)
-14.5%
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter annual electricity (kWh).
- 2Enter annual natural gas (therms).
- 3Enter building square footage (sq ft).
- 4Enter building type.
- 5Read your site eui on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
EUI is the standard metric for comparing building energy performance regardless of size, and it's required input for ENERGY STAR Portfolio Manager scoring, many city benchmarking ordinances (NYC Local Law 84, Chicago, Seattle), and most green building certifications. This calculator converts your annual electricity and gas consumption into site EUI (kBtu per sq ft per year) and compares it against typical ENERGY STAR medians by building type, so you can see roughly where you stand without pulling a full Portfolio Manager report. Site EUI counts energy delivered to the building; source EUI (which Portfolio Manager also reports) accounts for generation and transmission losses upstream and is usually 2-3x higher for electricity-heavy buildings. Cities with benchmarking mandates increasingly attach financial penalties to buildings that miss EUI targets, so this number has moved from a nice-to-have sustainability metric to a compliance and asset-value figure for commercial real estate.
Worked example
Using the values the calculator loads with:
Inputs
- Annual electricity: 800000 kWh
- Annual natural gas: 30000 therms
- Building square footage: 100000 sq ft
- Building type: Office (median ~67 kBtu/sq ft)
Results
- Site EUI: 57.3
- Total annual energy: 5,729,600
- ENERGY STAR median for type: 67
- vs. median (positive = worse): -14.5%
What each field means
Inputs
- Annual electricity (kWh)
- The annual electricity used in the calculation, measured in kWh. Starts at 800000 kWh so you have a working example on load.
- Annual natural gas (therms)
- The annual natural gas used in the calculation, measured in therms. Starts at 30000 therms so you have a working example on load.
- Building square footage (sq ft)
- The building square footage used in the calculation, measured in sq ft. Starts at 100000 sq ft so you have a working example on load.
- Building type
- Pick the option that matches your situation — the maths changes per option. Choices: Office (median ~67 kBtu/sq ft), Retail (median ~68 kBtu/sq ft), Hospital (median ~230 kBtu/sq ft), K-12 school (median ~57 kBtu/sq ft), Hotel (median ~90 kBtu/sq ft).
Results
- Site EUI
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total annual energy
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- ENERGY STAR median for type
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- vs. median (positive = worse)
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What's the difference between site EUI and source EUI?
Site EUI measures energy delivered to your meter. Source EUI multiplies electricity by a conversion factor (about 2.8-3.1x in the US) to account for generation and transmission losses, so an all-electric building looks worse on source EUI than a gas-heavy one even at identical site EUI. Regulatory benchmarking ordinances typically use both.
My city requires benchmarking — is this the same as Portfolio Manager?
This gives you a quick estimate, but official benchmarking ordinances require submission through EPA's ENERGY STAR Portfolio Manager tool, which pulls exact billing data and applies weather normalization. Use this calculator to sanity-check your number before or after you run the official report.
How much can retrofits realistically move my EUI?
LED lighting retrofits alone typically cut 5-15% of site EUI in older buildings; HVAC upgrades and controls optimization can add another 10-20%. Deep energy retrofits (envelope plus systems) targeting 30-50% reduction usually require a multi-year capital plan, not a single project.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Building Energy Use Intensity (EUI) Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/building-eui
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/building-eui" target="_blank" rel="noopener">Building Energy Use Intensity (EUI) Calculator — RevenueLab</a> (2026).</p>
Source: [Building Energy Use Intensity (EUI) Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/building-eui) (2026).