Methodology & Data Sources
Every figure on Square Foot Price Calculator should be checkable by the person reading it. This page says where each one comes from, what it measures, and when it was last verified.
Benchmark data verified September 2026What our city benchmarks are — and are not
These are our own compiled benchmarks, not a government series. The 52 metro medians used across this site are maintained by us for like-for-like comparison. No federal agency publishes a median price-per-square-foot series at metro level, so any page claiming one as the source for figures like these is mis-citing it.
An earlier version of this site credited the Federal Reserve Bank of St. Louis (FRED) for these medians. That attribution was wrong and has been removed from the calculator, the city pages, the conversion table and our machine-readable llms.txt. Our national and construction figures still come from named primary sources, listed further down.
What the number measures
A benchmark of $220/sq ft means the median residential sale price divided by finished, above-grade living area — the same basis a US appraiser works from. Getting this definition right matters more than the decimal places:
- Included: finished, above-grade, heated and cooled interior floor area, measured to the ANSI Z765-2021 standard used by Fannie Mae and lenders. See our guide to what counts as finished living area.
- Excluded: garages, unfinished basements, attics, porches, and any below-grade space — regardless of how a listing presents them. Including them artificially lowers the price per square foot.
- Excluded: land value, for every construction cost figure we publish. Build costs and land costs move independently and should never be blended into one per-foot rate.
- Commercial figures follow BOMA definitions instead, where rentable square footage includes a share of common area. Our usable vs rentable guide explains why the two are not interchangeable.
Precision, rounding and what the spread means
Metro medians are published as whole dollars per square foot. They are deliberately not carried to cents: the underlying spread within any metro is far wider than a cent, and a precise-looking number would imply accuracy the figure does not have. Across the 52 metros we track, the range currently runs from $1050/sq ft in San Francisco, CA to $145/sq ft in Tulsa, OK.
Use these as a comparison baseline, not a valuation. A benchmark tells you whether a listing is an outlier for its market. It cannot tell you whether the outlier is a bargain or a building with a failing roof — that is what an inspection and an appraisal are for.
Primary sources
National market and construction figures come from these sources, cited with their release dates wherever they appear:
| Source | What we take from it | Vintage |
|---|---|---|
| US Census Bureau — Characteristics of New Housing | New single-family home size and average price per square foot, including the 2015–2025 series showing size down 11.6% while price per square foot rose 71.9% | Released Jul 2026 |
| US Census Bureau — Monthly New Residential Sales | Median and average new-home sale prices, monthly | Jul 2026 data |
| National Association of Home Builders (NAHB) | Cost of Construction Survey, framing lumber prices, and builder-reported tariff cost effects per home | 2026 |
| Federal Register / USTR | Section 232 and softwood lumber duty rates used in our tariff cost-per-square-foot analysis | In force 2026 |
| ANSI Z765-2021 / BOMA | Measurement standards defining what area may be counted | Current editions |
Update cadence
Benchmark data carries the month it was last verified — currently September 2026 — on the calculator, the conversion table and all 52 city pages. We review the full dataset monthly. When a figure changes, the verification date changes with it; when a review finds no change, the date still advances so you can tell “checked and unchanged” from “never rechecked”.
This is a deliberate contrast with how the rest of this category operates. Several widely-used price-per-square-foot calculators carry no verification date at all, and at least one has gone more than two years without an update while still presenting its figures as current.
Corrections
If a number here is wrong, we want to fix it and say that we did. The FRED attribution described at the top of this page is a live example: it was corrected sitewide rather than quietly deleted, and it is documented here so anyone who saw the old citation can see what replaced it.
Report an error through our contact page. Material corrections to a published figure are noted on the affected page. Our editorial guidelines cover the review process in full.
Known limitations
- Metro-level only. We publish no ZIP-code or neighbourhood medians, because the within-metro spread is large enough that a single metro figure should not be presented as one.
- Residential resale basis. Metro medians reflect existing-home sales. New-construction price per square foot is a different measure on a different basis (it excludes land) and the two are not directly comparable — a distinction that trips up most published comparisons.
- No forecast. Nothing here projects future prices. Every figure is backward-looking as of its verification date.
- Not an appraisal. These tools are for comparison and budgeting. They are not a valuation, a lending decision, or investment advice.
Questions about a specific figure? Get in touch and tell us which page and which number — we will point you at its source or correct it.