How we compute NYC paycheck taxes
Federal brackets from IRS Rev. Proc. 2025-32, NY State from IT-201-I, NYC tax, FICA, SDI, PFL — with the actual algorithm and every primary source linked.
Methodology
Every number in every SuperNYC tool traces back to a primary source. These pages document the sourcing and the algorithm behind each tool — what we use, where it comes from, when it was last verified, and what we don't yet cover.
Why we publish methodology
NYC has a lot of calculators online. Most of them are wrong in small ways — generic effective-rate approximations for taxes, lazy 30%-of-income rules for affordability, stale subway data, made-up scam scores. The way SuperNYC differs is that every constant in the code traces to a published primary source: IRS revenue procedures, NY Department of Taxation IT-201 instructions, NYC DOT calendars, MTA GTFS-Realtime feeds, NYPD and FTC consumer advice. These methodology pages exist so you can verify that for yourself.
We re-verify the underlying data on a schedule (tax tables annually each January, parking calendar each November, rents quarterly, MTA endpoints on outage) and the dates below reflect the most recent verification.
How we measure NYC neighborhood rents
Median 1-bedroom asking rent per neighborhood, aggregated from current listings via Leaseswap NYC (StreetEasy + RentHop + Craigslist + LeaseBreak). Quarterly re-verification.
How we read MTA subway alerts
MTA's GTFS-Realtime alerts feed (the same one new.mta.info uses), parsed by the official Service Status Box algorithm — sort by Mercury 'sort_order', surface the largest.
How we determine alternate-side parking status
NYC DOT's 2026 annual calendar (67 planned suspensions) is the source of truth. Emergency suspensions for snow/parades are out of scope in v1 — what that means and how to check.
How we score apartment listings for scam risk
11 heuristics calibrated so no single false positive can push a listing into 'high risk' on its own. Every rule cites an NYPD, FTC, NY DOS, or StreetEasy source.
Corrections and updates
If you find a number on any SuperNYC tool that disagrees with a primary source you can cite, email hello@supernyc.com with the URL of the source. We respond to every correction request — and if you're right, we'll fix the underlying data file, bump the methodology page's "Last verified" date, and note the change in our commit history. We don't claim infallibility; we claim traceability.