Zoning feasibility vs. site planning: RunEnvelope vs. TestFit
TestFit is a generative site-planning and feasibility engine used across many U.S. markets to lay out buildings, parking, and units. RunEnvelope is NYC-native: it starts from the NYC Zoning Resolution and answers what’s legally buildable as-of-right before anything is laid out.
TestFit shines at rapid, configurable site layouts and unit yield for a design team. RunEnvelope is built specifically around NYC zoning, resolving the as-of-right envelope, City of Yes programs and air rights for a specific lot. They solve different halves of the problem, and many NYC teams use both.
Feature by feature.
| Capability | RunEnvelope | TestFit |
|---|---|---|
| NYC Zoning Resolution encoded | RunEnvelopeYES | TestFitGeneric zoning inputs |
| As-of-right FAR & buildable SF | RunEnvelopeYES | TestFitYES |
| 3D massing model | RunEnvelopeYES | TestFitYES |
| Generative site/parking layouts | RunEnvelopeNO | TestFitYES |
| Typical-floor sketch plans & unit mix | RunEnvelopeYES | TestFitYES |
| City of Yes programs integrated | RunEnvelopeYES | TestFitNO |
| Air rights & assemblage analysis | RunEnvelopeYES | TestFitNO |
| Single report, no subscription | RunEnvelope$149 | TestFitNO |
Sources Based on publicly available information as of July 2026. Features change; verify current capabilities with each vendor.
Where each one wins.
Where RunEnvelope wins
- ■NYC-native: the Zoning Resolution is encoded, so the as-of-right answer reflects actual bulk, yard, and sky-exposure rules, not generic inputs.
- ■City of Yes, air rights, and assemblage modeling built in.
- ■Every figure cited to the Zoning Resolution section that produced it.
- ■A single lot-specific report for $149, with no subscription and no enterprise onboarding.
Where TestFit is stronger
- ■Best-in-class generative site planning: buildings, parking, and unit layouts in seconds.
- ■Works across many U.S. markets, not just NYC.
- ■Deep design-team workflows for iterating physical layouts and yield.
- ■Strong for suburban and low-rise site planning where layout drives the deal.
Frequently asked.
Is RunEnvelope a TestFit alternative for NYC?
For NYC as-of-right feasibility, yes. TestFit is a cross-market generative site planner; RunEnvelope encodes the NYC Zoning Resolution and answers what’s legally buildable, and how it masses on a specific lot.
Does RunEnvelope do generative site layouts like TestFit?
RunEnvelope focuses on the zoning envelope and typical-floor sketch plans that follow from NYC bulk rules, rather than open-ended generative site/parking layout. For dense NYC lots, the binding constraint is usually zoning, which is what RunEnvelope is built to resolve.
Can I use both?
Many NYC teams do: RunEnvelope to establish the as-of-right envelope, TestFit to iterate physical layouts within it. RunEnvelope’s $149 single report makes it easy to add the NYC-zoning layer.
See what RunEnvelope shows on your lot.
An architect-grade zoning study: as-of-right FAR, 3D massing, per-floor sketch plans and a Zoning Resolution citation on every figure. One report from $149, no subscription.