# Pencilwrite

> Pencilwrite is real estate underwriting software. A few inputs in, a full underwrite out:
> cap rate, cash-on-cash, DSCR, true ROE, after tax return, and a ready to send offer.
> One model for rentals, BRRRR, flips, and wholesale. Built by active investors in Minnesota.

## Free Minnesota rent data

- [MN Rent Explorer](https://pencilwrite.com/rents/): rent for 914 Minnesota ZIP codes. HUD fair market
  rents FY2021 to FY2026, Zillow market asking rents for 172 ZIPs, year over year trends,
  bedroom level breakdowns. Updated monthly. Each ZIP has its own page at /rents/<zip>/.
- County rollups: every Minnesota county with SAFMR ZIP data has its own page at /rents/county/<slug>/,
  with a county median 2 bedroom FMR, market rent, a ZIP table, and the biggest year over year movers.
  87 counties covered, for example https://pencilwrite.com/rents/county/hennepin/.
- [Section 8 rent spread](https://pencilwrite.com/rents/section-8/): HUD fair market rent versus Zillow market rent
  for 172 ZIP codes with both signals, spread in dollars and percent, flags ZIPs where FMR
  meets or beats market rent (voucher competitive). 97 qualify.
- [Methodology](https://pencilwrite.com/rents/methodology/): what each measure is, HUD SAFMR 40th percentile on a
  fiscal year basis, Zillow ZORI as a smoothed all sizes index, ACS median gross rent, how the spread and
  the voucher competitive flag are computed, update cadence, and the known limits. Read this first.
- Statewide median 2 bedroom fair market rent is $1,090 for FY2026.
- Sources: HUD SAFMR, Zillow ZORI, US Census ACS, GeoNames. Last data update 2026-09-05.
- [Full plain text dataset summary](https://pencilwrite.com/llms-full.txt): statewide and county tables, the Section 8
  summary, and the definitions, in one file.

## API for agents

Free static JSON, no key, no rate limit, CORS open to any origin. Docs at https://pencilwrite.com/developers/,
machine readable contract at https://pencilwrite.com/openapi.json.

- https://pencilwrite.com/api/v1/index.json: every ZIP code, one row each, with FMR by bedroom, year over year
  change, latest market rent, spread, and the voucher competitive flag.
- https://pencilwrite.com/api/v1/zip/<zip>.json: one ZIP in full, the FMR series by fiscal year and bedroom, the
  monthly market rent series, ACS medians where published, and the six nearest ZIP codes.
- https://pencilwrite.com/api/v1/county/<slug>.json: one county, medians plus a row per ZIP code.
- https://pencilwrite.com/api/v1/section-8.json: the FMR versus market rent spread table plus a summary block.
- https://pencilwrite.com/api/v1/meta.json: counts, source vintages, license, citation, endpoint list. Poll this and
  compare generated_at instead of refetching every ZIP.

License: CC BY 4.0, https://creativecommons.org/licenses/by/4.0/. Commercial use is fine, attribution is the only condition.
Cite as: Pencilwrite MN Rent Data, pencilwrite.com/rents/
MCP server: coming soon at mcp.pencilwrite.com

## Product

- [Home](https://pencilwrite.com/): what Pencilwrite does and early access signup.
- [Sample underwrite](https://pencilwrite.com/report): a full example deal report.
- [Developer docs](https://pencilwrite.com/developers/): the rent data API.