Source-backed estimates
The tax-sensitive tools link to IRS sources and explain the assumptions behind each estimate.
Free tools for U.S. small businesses
Calculators for expenses, deductions, taxes, and contractors
Estimate the numbers owners search for, then use Cadus to keep the underlying receipts, mileage, income, invoices, contractor records, and reports organized.
Free mileage tool
Mileage Deduction Calculator
Estimate a 2026 business mileage deduction using the IRS 72.5 cents-per-mile rate, then track mileage, expenses, receipts, and tax records in Cadus.
Open calculator
Free home office tool
Home Office Deduction Calculator
Estimate a simplified home office deduction using the IRS $5 per square foot method, up to 300 square feet, and organize records in Cadus.
Open calculator
Free contractor tool
1099 Contractor Payment Tracker
Track contractor payments against the current 2026 Form 1099-NEC planning threshold, then organize W-9s, expenses, reports, and records in Cadus.
Open calculator
Free quarterly tax tool
Quarterly Tax Set-Aside Calculator
Estimate how much to set aside for quarterly taxes from self-employed profit, see 2026 estimated tax due dates, and organize records in Cadus.
Open calculator
Built for records
Cadus helps turn estimates into organized business records across expenses, receipts, income, invoices, mileage, and exports.
Planning, not filing
These calculators help with planning. Final filing decisions should use tax software, payroll software, or a qualified professional.