Data sources & methodology
25 calculators ship with 57 labelled default values drawn from 20 cited sources, of which 8 URLs returned a successful response to an automated check. Registry last reviewed January 2026. This page is the complete registry. It exists because a calculator is only as trustworthy as its inputs, and because we would rather tell you that a number is a convention than dress it up as analysis.
What we do not claim
- No primary research. We do not run surveys, and no figure on this site comes from a private dataset. Ranges are attributed to the organisation that published them.
- No advice. A default is an illustration of how a model behaves, not a recommendation for your deal, your payroll or your pricing.
- No currency guarantee. Fee schedules and statutory rates change. Each source carries an edition or date, and the review cadence below says when we re-check it.
Four kinds of basis
| Basis | What it means | How to treat it |
|---|---|---|
| Statutory / regulatory | Fixed by law or a regulator | Cite and verify annually; the structure is stable, the numbers move |
| Vendor rate card | Published by the party that charges the fee | Verify against your own account — category and volume change the rate |
| Market survey | A published benchmark survey (a range, not a fact) | Use as a sanity band; replace with your own observed data |
| Rule of thumb | An industry convention with no authoritative source | Treat as a starting hypothesis only — the weakest basis we use |
Verification status
Citation links are rendered as links only when an automated HTTP request returned a successful response. Institutional sites frequently block automated requests, so several authoritative sources are cited by name and document title without a link until a person confirms the URL in a browser. A plain citation is not a weaker source — it is an unverified link, and we do not publish those.
Review cadence
- Marketplace and payment fees: quarterly, and after any announced change.
- Statutory rates (FICA, FUTA, overtime thresholds): annually, when the new tax year tables publish.
- Workers’ compensation and SUTA ranges: annually — these are state and class specific, and we never present them as your rate.
- SaaS and market benchmarks: annually, when the survey editions we cite are refreshed.
- Every calculator: re-run and re-verified after any model change; the page “Updated” date changes with it.
How to replace a default with your own number
- Change the input in the calculator, or change the blue input cell in the downloaded workbook.
- Every downstream figure recalculates — no formula editing required.
- If a default is materially wrong for your business, treat it as a signal that the model’s assumption set needs localising, not that the model is broken.
Statutory / regulatory
Publication 15 (Circular E), Employer's Tax Guide
IRS · as of annual edition
Primary source for FICA employer rates, FUTA rate and the federal wage base.
www.irs.gov/publications/p15Contribution and Benefit Base
Social Security Administration · as of annual
Social Security wage base used to cap the 6.2% employer tax.
www.ssa.gov/oact/cola/cbb.htmlFact Sheet #23: Overtime Pay Requirements of the FLSA
US Department of Labor, Wage & Hour Division · as of current
Federal rule: hours over 40 in a workweek at 1.5x. Site blocks automated requests.
www.dol.gov/agencies/whd/fact-sheets/23-flsa-overtime-pay (unverified)Overtime FAQ
California DIR, Division of Labor Standards Enforcement · as of current
Daily overtime above 8 and 12 hours, and the seventh-consecutive-day rule.
www.dir.ca.gov/dlse/FAQ_Overtime.htm (unverified)Meal and Rest Periods FAQ
California DIR, Division of Labor Standards Enforcement · as of current
Meal period before the 5th hour, second before the 10th, and the premium for a missed break.
www.dir.ca.gov/dlse/faq_mealperiods.htm (unverified)Vendor rate card
Pricing
Stripe · as of current
Card processing rate used as the default payment fee in the e-commerce models.
stripe.com/pricingSelling on Amazon — pricing and referral fees
Amazon · as of current
Category referral fee percentages, including the 15% standard rate.
sell.amazon.com/pricingFBA fulfilment fee schedule (size tiers)
Amazon Seller Central · as of current
Size-tier definitions and shipping-weight bands. Requires a seller login to view.
sellercentral.amazon.com/help/hub/reference/GABBX6GZPA8MSZGWMarket survey
Employer Costs for Employee Compensation
US Bureau of Labor Statistics · as of quarterly
Benchmark for benefits and legally required benefits as a share of total compensation.
www.bls.gov/news.release/ecec.nr0.htm (unverified)Job Openings and Labor Turnover Survey (JOLTS)
US Bureau of Labor Statistics · as of monthly
Published separation and turnover rates by industry — the basis for our turnover ranges.
www.bls.gov/jlt/ (unverified)Occupational Employment and Wage Statistics
US Bureau of Labor Statistics · as of annual
Wage benchmarks by occupation and geography for the sample wages in our models.
www.bls.gov/oes/ (unverified)Workers compensation class codes and loss costs
NCCI and state rating bureaus · as of annual by state
Rates are per $100 of payroll and vary by class code and state. Always use your own carrier rate.
www.ncci.com/ (unverified)SaaS metrics benchmarks
Benchmarkit · as of latest annual edition
Source for the NDR, GRR, CAC payback and Rule of 40 ranges used as SaaS defaults.
www.benchmarkit.ai/State of the Cloud
Bessemer Venture Partners · as of latest annual edition
Cloud and SaaS operating benchmarks including the Rule of 40 framing.
www.bessemer.com/cloud-index (unverified)Primary Mortgage Market Survey
Freddie Mac · as of weekly
The reference for the illustrative mortgage rate in the rental defaults.
www.freddiemac.com/pmms (unverified)H.15 Selected Interest Rates
Federal Reserve · as of weekly
Risk-free rate context for cap-rate and cost-of-debt assumptions.
www.federalreserve.gov/releases/h15/New Residential Construction
US Census Bureau · as of monthly
Housing supply context; not used as a default in any model.
www.census.gov/construction/nrc/index.html (unverified)Short-term rental market data
AirDNA · as of monthly
ADR and occupancy benchmarking for the short-term rental defaults.
www.airdna.co/ (unverified)Standard / specification
G702 — Application and Certificate for Payment
American Institute of Architects · as of current edition
The nine-line structure replicated in the schedule of values workbook. AIA documents are copyrighted forms; we reproduce the arithmetic, not the form.
www.aiacontracts.com/contract-documents/25901-application-and-certificate-for-payment/ (unverified)Safe financing documents (pre-money and post-money)
Y Combinator · as of current
The standard SAFE forms our conversion logic follows: cap price versus discount price, whichever is lower.
www.ycombinator.com/documentsWhich defaults apply to which tool
Corrections
If a rate is out of date or a range is wrong, email models@sheetmodel.com with the page and the number. Verified corrections ship within two business days and the page’s updated date changes with them. We do not silently change figures.