About our data
Every number on PennyCheck comes from a real, verifiable source. This page explains where our data comes from, how we verify it, and what "Last verified" means on each tool.
Where our data comes from
We draw from three categories of primary sources. Every tool page lists its specific sources with links so you can verify the data yourself.
Government databases
State court filing fees, CMS Medicare provider utilization data, state health department discharge records, IRS tax tables, state business filing offices, and Department of Labor statistics.
Industry reports and surveys
Clio Legal Trends Report (attorney rates), American Bar Association fee surveys, state bar association data, Healthcare Bluebook (medical procedure pricing), and contractor industry surveys from trade associations.
Retail and market data
Current pricing from major retailers (Home Depot, Lowe's, Sherwin-Williams), manufacturer specifications, and published rate sheets from service providers.
How we verify data
Source identification
Before building any tool, we identify the most authoritative primary source for each data point. Government databases take priority over industry estimates, and industry reports take priority over individual provider quotes.
Cross-referencing
Data points are cross-referenced against at least two independent sources when available. If sources disagree, we use the more conservative estimate and note the range.
Formula testing
Every calculator has automated test cases that verify the formula produces correct output for known input combinations. These tests run before any tool is published and are re-run whenever data is updated.
Date stamping
Every tool displays a "Last verified" date — the date we last confirmed that all data points in that tool match their primary sources. This is not the date the tool was created; it is the date the data was last checked.
What "Last verified" means
The "Last verified" date on each tool page indicates when we last confirmed that every data point in the calculator matches its primary source. This includes filing fees, hourly rates, material costs, and any other figures used in the calculation.
We re-verify data when sources publish updates (e.g., annual fee schedule changes, new survey results) and flag tools for review if their data has not been verified within 12 months.
Limitations
- •Estimates are based on averages and medians. Your actual costs may be higher or lower depending on your specific situation, location, and provider.
- •Attorney rates, medical costs, and service prices vary significantly within the same state and even within the same city.
- •Our calculators do not account for every possible fee, surcharge, or cost component. Unusual circumstances may result in costs outside our estimated range.
- •Data from industry surveys may lag real-world pricing by 6-12 months. We note the source date on every tool so you can assess currency.
- •PennyCheck calculators are informational tools, not professional advice. Always consult a qualified professional for decisions involving legal, medical, or financial matters.
Found an error?
If you find a number that's wrong or outdated, we want to know. Include the tool name, the incorrect figure, and a link to the source with the correct data. We investigate all reports and update verified corrections within 48 hours.
Report a data correction