Every figure we got wrong, what's right now, and who would have seen it. They stay listed after they're fixed.
How we handle a mistake
Fix the math with a test first. A correction to a formula or table starts with an automated test that fails on the wrong number. That test then stays in the project, so the same mistake can't quietly come back.
Say what changed, with numbers. Each correction below gives the figure readers saw, the right one, and the pages that showed it. "Improved accuracy" isn't a correction notice.
Mark the page. Guides and glossary entries affected by a correction show a dated note linking here.
Keep it listed. Corrections stay here after the fix. The code change behind each one is linked.
A routine data update, like a new weekly mortgage rate, isn't a correction: the old number was right when it was published. Those are in the changelog.
Found one?
Tell us on the contact page or open an issue on GitHub ↗. It helps to include the page, the inputs you used, the number you saw, and where the right number comes from.
Corrections, newest first
Correction
Renters were charged a $500 move-in fee by default
The rent calculator and cost-to-move tool added a $500 building move-in fee to every lease signing. New York law bars landlords from charging that fee; it's a co-op or condo board charge.
What was wrong: Lease-signing cash on /rent/, /cost-to-move/, and every /rent/<price>/ page included a $500 "building / move-in admin fee".
What's right now: The fee defaults to $0 for renters (RPL §238-a(1)(a), added by the HSTPA in 2019), and is only for renting a unit in a co-op or condo building. Lease-signing totals dropped by $500. Co-op and condo buyers still pay their building's move-in deposit or fees.
NY State 6.85% bracket ended too high for single and head-of-household filers
The Required Salary calculator reused the married-filing-jointly threshold for single and head-of-household filers.
What was wrong: NY State's 6.85% bracket ran to $2,155,350 for every filing status, so income between about $1.08M and $2.16M (single) was taxed at 6.85% instead of 9.65%.
What's right now: The bracket ends at $1,077,550 for single filers and $1,616,450 for head of household, per the 2026 IT-2105-I worksheets. Only results above about $1.08M of income changed.
The income limits behind affordable-housing eligibility were labeled as the figures HPD uses, but were about 22% lower than HPD's published 2026 chart.
What was wrong: 100% AMI for 3 people was $124,700 (4 people: $138,550), so households were shown at a higher AMI percentage than HPD would assign. A 3-person household earning $150,000 showed 120% AMI.
What's right now: The table now matches HPD's 2026 New York City Area AMI chart: $152,700 for 3 people and $169,600 for 4. That household is at 98% AMI. Bands, eligibility, and max rents per band moved with it.
Compare and Reality Check skipped PMI below 20% down
The comparison dashboard and Reality Check had their own copy of the buying math, which left out private mortgage insurance.
What was wrong: Below 20% down, /compare/ and /reality-check/ overstated what you could buy. With the default profile at 10% down: co-op $386,066 and condo $511,957.
What's right now: Both now run the calculators' own engine, PMI included: $354,800 and $470,495 for that profile, matching /coop/ and /condo/. At 20% down or more, nothing changed.
The income and price pages summed three of the co-op calculator's five fixed closing fees.
What was wrong: Co-op closing costs and cash needed on every /buy/<price>/ and /income/<amount>/ page left out the $1,000 move-in deposit and $800 of other fixed fees. /buy/500000/ showed $154,923 of total cash.
What's right now: They now include all five fees, matching /coop/: /buy/500000/ shows $156,723. Condo figures were unaffected.