How We Score Buildings

Our algorithm analyzes 70+ million public records across 26 data sources to produce one comprehensive score for every building in New York City. Here's what goes into it.

Before you sign a lease, know what you're walking into.

Covering every building in New York City

858,000+
Buildings analyzed
70M+
Records analyzed
26
Data sources
Daily
Update frequency

The Grading Scale

Every building receives a score from 0 (best) to 100 (worst), mapped to a letter grade. Lower is better — think of it like a risk score.

A
Clean(0–12)

Minimal or no issues on record. Well-maintained with a strong compliance history.

B
Fair(13–30)

Some minor issues, nothing unusual. Typical for a reasonably managed building.

C
Watch(31–50)

Mixed record worth reviewing. Patterns may be emerging across one or more components.

D
Poor(51–70)

Multiple unresolved issues across several dimensions. Declining trajectory.

F
Distressed(71–100)

Serious violations, safety concerns, or systemic neglect. Immediate attention warranted.

The Seven Scoring Dimensions

Each building's score is composed of seven scoring dimensions. The weights reflect each dimension's predictive importance — developed through extensive analysis of building outcomes across all five boroughs.

Living Conditions

Are residents living in safe, code-compliant conditions?

Building Safety

Is the building structurally sound with up-to-date safety compliance?

Complaint Burden

How often do residents and neighbors report issues — and are the patterns meaningful?

Management Quality

Is the building properly registered, responsive to issues, and meeting regulatory requirements?

Financial Health

Does the owner have the financial capacity to maintain the property?

Maintenance History

Is there evidence of proactive upkeep and passing inspections?

Legal & Enforcement

Has the building faced litigation, enforcement actions, or emergency orders?

Recent Improvements

We continuously refine our algorithm to be fairer and more accurate. Here are the latest improvements to how we calculate scores.

Outlier Protection

We detect and adjust for complaint patterns that don’t reflect actual building conditions. Scores are robust against anomalous filing patterns.

Smarter Data Scoping

Historical records are weighted by recency — older records carry proportionally less weight, ensuring current conditions are what matter most.

Context-Aware Scoring

Buildings actively addressing issues (like ongoing repairs) are recognized for taking action, not penalized for having a problem.

Limited Data Indicator

Buildings with insufficient public records now display a Limited Data badge instead of receiving a potentially misleading score.

Peer-Group Comparison

A 6-unit pre-war walkup shouldn't be compared to a luxury high-rise. We compare buildings against similar properties so every score reflects realistic expectations for that category of building.

Each building's score is contextualized against similar buildings by type, age, and size, so you can see whether it's performing above or below its peers.

Data Sources

We ingest data daily from 26 official public sources. Every building in NYC is covered — not a sample, not a subset.

HPD Violations
HPD Complaints
HPD Registrations
HPD Litigation
HPD Bedbug Reports
HPD Contacts & Owners
DOB Violations
DOB Complaints
DOB Permits
DOB Approved Permits
DOB Inspections
DOB NOW Inspections
DOB Elevator Inspections
DOB Facade FISP (LL11)
DOB Certificates of Occupancy
ECB Violations
DHCR Rent Stabilization
DOF Tax Liens
DOF Tax Rolls
311 Service Requests
FDNY Vacate Orders
Housing Court Records
DOH Health Inspections
LL84 Energy Benchmarking
ACRIS Transactions
ACRIS Lot Records
Boiler Inspections
Water Tank Inspections
PLUTO Property Data

We also maintain historical snapshots of every building over time. This allows us to track score trajectories — whether a building is improving or declining — data that doesn't exist anywhere else.

Frequently Asked Questions

Why does my building have a low score?

Health scores reflect the cumulative impact of multiple risk signals across seven scoring dimensions. A low score typically indicates a pattern of unresolved issues. Check the building's score breakdown to see which areas are driving the score.

Can I dispute a score?

Our scores are calculated from official public data sources. If you believe there's a discrepancy, contact us at data@openstoop.com with the building address and details. We investigate every report.

How often are scores updated?

Our data pipeline ingests new information daily from 26 public sources. Scores are recalculated regularly to reflect the latest available data.

What makes OpenStoop different from other tools?

Most tools show you raw violation lists. We synthesize 26 data sources into one score that factors in severity, recency, patterns, and context — so you don't have to. We also track how buildings change over time.

What does 'Limited Data' mean?

Some buildings have very few public records — new construction, small buildings, or properties that simply haven't generated much regulatory activity. Rather than assign a potentially misleading score, we flag these with a Limited Data indicator.

How do I get started?

Search any NYC address to instantly view its building health score and key data. No account required.