SnagFlat
Rent stabilization
Flags buildings that are registered as rent-stabilized or hold a J-51 / 421-a tax benefit that requires stabilization. Shown as stabilized, likely, not stabilized, or unknown — never overstated.
Chrome extension · NYC only
Triage NYC listings at a glance.
See which NYC listings are likely rent-stabilized — and which way they face — at a glance, right on StreetEasy. SnagFlat reads the listing you're already viewing and adds small badges so you can scan a results page without clicking into every apartment.
Free. No account. Works on StreetEasy. Badges are building-level signals from public NYC data — informational, not a guarantee. Read why that matters.
🏠 Likely rent-stabilized
☀ Faces SW
☀ 2–11h sun
🌿 Quiet street
📐 ~960 ft²/unit
What the badges tell you
Each badge is a quick, honest signal — and each one explains its basis and caveats when you click it. Rent stabilization is the headline; the rest help you compare listings faster.
Orientation
Which way the building faces and whether a south exposure is even possible, derived from the building's footprint — not a claim about your specific unit.
Sun hours
An estimate of direct-sun hours, given as a low-floor vs high-floor range, computed against neighboring building heights. The range keeps the floor-dependence honest.
Busy or quiet street
A heuristic from the street name — avenues and major crosstown streets read as busier, ordinary side streets as quieter. Actual noise varies by block, floor, and which way you face.
Average unit size
The building's average residential square footage (total residential area ÷ units). It's a building average, not this unit's size — NYC has no authoritative per-unit square footage for rentals.
Filter the results page
On a search-results page, hide listings by badge — e.g. show only rent-stabilized, quiet-street, or 6h+ sun. Your selection sticks across pages.
Demo coming soon — a short clip of the badges on a StreetEasy results page.
How it works
SnagFlat is a thin client. The extension reads the address off the listing page and asks our backend; the backend does the lookups against public NYC data. No heavy datasets ship in your browser.
1
Read the address
On a supported listing, the extension extracts the address (and borough / zip) from the page you're already viewing. That's the only thing it sends.
2
Find the building
Our backend geocodes the address to a NYC building identifier (its BBL) using NYC Planning's GeoSearch, recording how confident the match is.
3
Look up open data
Keyed by that building ID, we check public NYC datasets and JustFix's Who-Owns-What for registered stabilized units, J-51 / 421-a benefits, footprint, and neighbor heights.
4
Show honest badges
We return a status with its basis and an explicit caveat. The extension draws the badges and caches the answer locally so revisiting a listing doesn't re-query.
What SnagFlat does — and doesn't — prove
Rent stabilization is determined at the individual unit level, and the public data lags reality. We're careful not to overstate what a badge means, because people make housing decisions based on this.
- Badges are building-level. "This building is registered as rent-stabilized" is not the same as "this specific apartment is stabilized." A unit can have been deregulated even in a stabilized building.
- Public data can lag. Registrations and tax-benefit records are updated on their own schedules and may not reflect the current state of a building or unit.
- It's informational, not legal advice. SnagFlat is a triage tool. It is not a guarantee of any unit's status and shouldn't be the sole basis for a housing decision. Verify with DHCR/HCR and a professional before you rely on it.
- We say "unknown" when we mean it. When the data is inconclusive — for example, an older building with no registration signal — we show unknown rather than a confident-but-wrong answer.
- NYC only, for now. Coverage is limited to New York City at launch, because the datasets are NYC-specific.
More detail is on the disclaimer page, and every badge repeats its own caveat in the detail panel when you click it.
Add SnagFlat and scan smarter
Install it once, then browse StreetEasy like normal. The badges appear on their own.