1. Find Your Building by Address or BBL
Search with an NYC street address or the property's 10-digit borough-block-and-lot number, then confirm the building. A BBL is NYC's borough-block-and-lot identifier for a tax lot. A BIN is NYC's Building Identification Number for an individual building.
Address matching and multiple BINs
One lot can contain several buildings with different LL97 pathways. Check the matched address, BBL and BIN against your records, and select the building you mean.
A street entrance and a reporting address may differ. If the address search misses, try the BBL and check the candidate BINs.
Keep a copy of your result
Review the data year, assumptions and missing fields, then keep a copy of the summary. Keep the BIN, pathway and baseline year with it, especially when several buildings share a lot.
2. Coverage, Area, Property Type and Owner
The covered-buildings record indicates a preliminary pathway. Reported use areas and energy quantities drive the estimate.
Preliminary coverage
Read the pathway and start year alongside the selected BIN. The 2026 NYC DOB Covered Buildings List is a preliminary reference, subject to corrections and approved changes. If your approved pathway differs, keep that evidence with the calculation.
Report GFA vs. DOF reference area
Use reported gross floor area and the area assigned to each property use. Department of Finance lot area is a coverage reference only. A mixed-use property needs the area of each use, beyond its largest one.
Check whether the result covers a building, a reporting property or a tax-lot group. Parent properties and shared meters can block a separate building estimate.
Public owner names are masked under our display policy.
3. Compare Both Compliance Periods
Both periods use the same baseline energy quantities under each period's limits and coefficients.
2024–2029 and 2030–2034
Each view shows the limit, scenario emissions, excess tonnes, indicative annual penalty, baseline energy year and calculation year.
For 2024 and 2025, the calculator uses ESPM limits only, which may produce a higher estimate. Method, use limits and energy coefficients depend on the calculation year.
The reduction needed is the positive emissions gap divided by scenario emissions. If emissions or the limit is unavailable, the percentage is unavailable too.
Annual estimate vs. period total
An annual estimate covers one applicable year. A total for the six-year or five-year period needs a year-by-year scenario that respects the pathway's start year.
A whole-building scenario is not a per-apartment bill; allocation follows the building's own arrangements.
Buildings over the 2030 limit need HVAC work
A free account shows the five newest New York signals. The full LL97 list with owners and estimated penalties is on the Pro plan.
Find NYC buildings over the 2030 limit4. How the Calculator Works
The calculation adds use-specific emissions allowances, converts each energy quantity into emissions, then compares the two totals. Use the input summary to check the energy year, units and assumptions.
Use-specific area limits
For each property use, multiply its reported floor area by the applicable emissions-intensity limit, then add the allowances. Area is in square feet. The limit is in metric tonnes of carbon dioxide equivalent per year (tCO2e/year).
Each use needs an explicit mapping to the applicable rule. Parking and shared-system boundaries need their own treatment. If use areas don't reconcile with gross floor area, relabelling a use as "office" hides the problem.
Energy coefficients and units
Each fuel or energy carrier uses its own coefficient and unit. Electricity in kWh can't be entered as kBtu, and therms need a documented conversion. Baseline quantities stay fixed across both periods unless you change the scenario.
The steps follow the NYC DOB emissions rules and annual excess-emissions rate:
| Step | Calculation |
|---|---|
| Annual limit | Sum of each use area × its applicable intensity limit |
| Gross emissions | Sum of each energy quantity × its applicable coefficient |
| Net emissions | Gross emissions minus supported, documented eligible deductions |
| Excess emissions | Greater of zero or net emissions minus the annual limit |
| Indicative annual penalty | Excess emissions × $268 |
The $268 multiplier is the NYC DOB Article 320 annual excess-emissions basis.
Synthetic teaching example
Synthetic teaching example: assume an annual limit of 500 tCO2e and net emissions of 550 tCO2e. The excess is 50 tCO2e. 50 × the DOB rate of $268 gives an indicative annual penalty of $13,400/year.
Deductions and assumptions
The baseline assumes unchanged consumption and no unverified deductions or approved adjustments. A deduction needs evidence of eligibility before it reduces the result.
5. Interpret Your Covered-Building Pathway
The pathway sets which years apply before any annual estimate. A building can be covered by LL97 without using Article 320 annual limits in either displayed period.
Source for the pathway years below: NYC DOB coverage and pathways.
| Listed pathway | Treatment in this calculator |
|---|---|
| Article 320 beginning in 2024 | Estimate supported applicable years |
| Article 320 beginning in 2026 | Earlier years marked not applicable |
| Article 320 beginning in 2035 | Annual penalty N/A for both target periods |
| Article 321 one-time compliance | Article 320 annual penalty N/A |
Article 320 start years
A 2026 start makes earlier years inapplicable. A 2035 start puts both periods outside the annual calculation.
Article 321 and approved changes
Article 321 is a separate compliance pathway, so the Article 320 annual penalty is N/A. Keep evidence of an approved pathway change with the building's records.
See which buildings are on a retrofit path
A free account shows the five newest New York signals. The full LL97 list with owners and estimated penalties is on the Pro plan.
See NYC buildings with LL97 exposure6. For Commercial HVAC Contractors
Use an emissions gap to prioritize investigation, then confirm the building's actual systems and needs.
Commercial filters and emissions gaps
Compare commercial use, area, pathway start year and baseline year. Gas or steam consumption can shape site-visit questions.
Paid contractor research uses supported baseline scenarios to find buildings worth investigating. Keep the estimate label and dates with each result.
Owner entities and permits
Treat an owner entity as record context. Institutional details in a paid workspace need source evidence.
Permit evidence needs its own source and date. Confirm authority and scope with the owner before proposing work.
"Over the limit" in a 2030 scenario is not an issued violation.
7. For Owners and Facility Managers
Use the calculation to scope work and check data.
Owners: scope work and request quotes
Put the building, pathway, baseline year and assumptions in your project brief. State whether you need an assessment, operational improvements or a replacement proposal.
Ask bidders to separate investigation and design from construction. Ask them to explain the consumption assumptions behind proposed reductions. Electrical capacity, access and operating hours may affect scope.
Facility managers: fix data and plan operations
Reconcile a full year's bills with the reporting boundary. Check missing meters, fuel units and changes in property use before running a reduction scenario. A total energy figure without its carrier breakdown may not support the calculation.
Record each correction with its source document. The input summary shows your engineer which fields you supplied.
Reach owners before they retrofit
A free account shows the five newest New York signals. The full LL97 list with owners and estimated penalties is on the Pro plan.
See NYC buildings that need retrofits8. Fill In Missing Numbers in Manual Mode
Manual mode lets you edit supported inputs and marks each changed field for comparison with imported data.
Start with the prefilled record
Switch to "Enter my own data" and review the prefilled identifiers, use areas and energy quantities. Confirm the baseline energy year. A report submitted in one year may describe the previous year's consumption.
Enter missing use areas in square feet and each annual energy quantity in its labelled unit. Use records for the same property boundary and year. Leave unknown values blank; enter zero only with evidence of no consumption.
Reconcile use areas with reported gross floor area, and the energy breakdown with the total.
Cases that need allocation evidence
Shared meters, campus reports and parent-child properties need a defensible allocation boundary. Add the allocation evidence and method to estimate one building on its own.
Article 321 and a 2035 Article 320 start use their own rules outside the annual calculation.
If the service is interrupted, the calculator keeps your input so you can run it again.
Why your building might not get an automatic estimate
About a quarter of covered NYC building groups have public records complete enough for an automatic estimate. The rest usually fall into one of three cases.
12,554 building groups
It follows a different LL97 path
Rent-regulated, affordable and some other buildings complete a set list of energy measures instead of meeting the emissions cap, so there is no emissions-based penalty to estimate.
Its public energy report is incomplete
The LL84 report is missing energy use, floor area or use types, or its numbers don't add up. If you have the building's utility bills, you can enter them.
Several buildings share one record
Campuses, shared meters and lots with several buildings report together, so one building's share can't be split out from public data.
A building can fall into more than one case, so the numbers overlap.
How we built this estimate: data, checks and every exclusion reason
25,882 groups have an LL84 report, and 7,316 of them pass every check. Every share on this page counts BBL groups.
| Reason an automatic estimate is unavailable | BBL groups |
|---|---|
| Non-Article 320 pathway | 12,554 |
| Energy breakdown does not reconcile | 5,496 |
| Missing energy use | 4,916 |
| Missing use areas | 4,802 |
| Missing reported gross floor area | 4,781 |
| Multiple LL84 properties | 4,766 |
| Multiple buildings without allocation | 4,435 |
| Campus boundary | 3,336 |
| Shared metering | 3,334 |
Another 243 groups pass every completeness check and still lack an estimate. Those 243 break down as: 143 use types outside the rule table, 93 missing use areas, 4 missing energy use and 3 unsupported energy types. Reasons overlap, so a group can appear in several rows. Your result lists the reasons attached to your record.
A non-Article 320 pathway is the most common reason a group has no automatic estimate
Show the data
| Reason an automatic estimate is unavailable | BBL groups |
|---|---|
| Non-Article 320 pathway | 12,554 |
| Energy breakdown does not reconcile | 5,496 |
| Missing energy use | 4,916 |
| Missing use areas | 4,802 |
| Missing reported gross floor area | 4,781 |
| Multiple LL84 properties | 4,766 |
| Multiple buildings without allocation | 4,435 |
| Campus boundary | 3,336 |
| Shared metering | 3,334 |
These figures measure data readiness, not LL97 compliance.
FAQ
Are there any tools or calculators for Local Law 97?
Yes. This LL97 calculator compares building emissions limits and indicative annual penalty scenarios after you confirm an NYC address or BBL. Check its input summary, baseline year and N/A reasons against NYC DOB's calculation rules.
Is this calculator free?
Yes. Results and the input summary need no account. Paid contractor research is separate.
Can I search by address or BBL?
Yes. Enter an NYC address or 10-digit BBL, then confirm the matched building. If several BINs share the lot, select the intended building. A failed search does not mean the property is outside LL97.
How are penalties estimated?
For a supported Article 320 year, positive excess emissions are multiplied by the NYC DOB rate of $268 per tonne.
Why do 2030 results differ from current emissions?
The comparison keeps baseline consumption unchanged but applies the later period's limits and coefficients. The 2030–2034 view is a scenario, not a forecast of future consumption.
Does a zero estimate mean full compliance?
No. A zero means no positive excess in that supported scenario. Reporting compliance and other obligations are separate tasks.
What if my building follows Article 321?
The result shows that pathway and marks the Article 320 annual estimate N/A. Use the Local Law 97 guide to review the compliance task.
What if energy data is missing?
Fill supported inputs in manual mode with one year's records for the same property boundary.
Can contractors use owner data to qualify leads?
Partly. Owner entities add context, but they aren't verified contacts or proof of purchasing intent.
Does the calculator file an LL97 report?
No. It provides a planning estimate and input summary. It doesn't submit a report to DOB, set an actual penalty or replace professional certification.