Net effective rent (NER) calculator
Net effective rent calculator: straight-line and discounted NER per SF after free rent, TI allowance and leasing commissions, with every step shown.
Commercial real estate calculators
FactLot has 26 calculators for lease economics, debt, valuation and returns. Each returns the value, every intermediate step with its formula, warnings, and a versioned formula ID, so an analyst or an AI agent can show exactly how a number was made. The TypeScript and Python libraries produce identical results, checked by shared test cases.
Debt sizing calculator (DSCR, LTV and debt yield)
Debt sizing calculator: maximum commercial loan under DSCR, LTV and debt yield tests, the binding constraint, stress scenarios and refinance shortfall.
CAM reconciliation calculator
CAM reconciliation calculator: tenant share of operating expenses with gross-up, controllable caps, admin fees, base year or expense stop, and balance due.
Yield maintenance and defeasance calculator
Yield maintenance and defeasance calculator: prepayment premium and total payoff for a fixed-rate loan, plus step-down and flat-percentage penalties.
ASC 842 lease remeasurement calculator
ASC 842 lease remeasurement calculator: new lease liability, ROU asset adjustment, gain, and the operating or finance lease schedule after a modification.
Weighted average lease term (WALT) calculator
WALT calculator: weighted average lease term remaining in years, weighted by leased area or annual rent, from any as-of date, with expired leases flagged.
Direct capitalization calculator (cap rate value)
Direct capitalization calculator: property value from NOI and a cap rate, or the cap rate a price implies, with reserves and lease-up deductions.
Equity waterfall calculator (LP/GP pref, catch-up and promote)
Equity waterfall calculator: LP/GP distributions with preferred return, catch-up, IRR hurdle tiers and promote, plus each party's IRR and multiple.
Every calculator
All of them run on the hosted MCP server and REST API, and offline in the SDKs.
| Calculator | Tool | Formula |
|---|---|---|
| Lease rent schedule | calc_rent_schedule | calc.rent_schedule@1 |
| Net effective rent (NER) | calc_net_effective_rent | calc.net_effective_rent@1 |
| Compare lease proposals | calc_compare_proposals | calc.compare_proposals@2 |
| Multifamily rent roll | calc_multifamily_rent_roll | calc.multifamily_rent_roll@1 |
| Retail percentage rent | calc_percentage_rent | calc.percentage_rent@1 |
| CAM / operating expense reconciliation | calc_cam_reconciliation | calc.cam_reconciliation@2 |
| CAM reconciliation for every tenant (batch) | calc_cam_reconciliation_batch | calc.cam_reconciliation_batch@1 |
| Capital expenditure recovery | calc_capex_recovery | calc.capex_recovery@1 |
| Loan sizing (LTV / DSCR / debt yield) | calc_debt_sizing | calc.debt_sizing@3 |
| Lease remeasurement (ASC 842, lessee) | calc_lease_remeasurement_asc842 | calc.lease_remeasurement_asc842@2 |
| Loan prepayment premium and defeasance | calc_prepayment_and_defeasance | calc.prepayment_and_defeasance@1 |
| Weighted average lease term (WALT) | calc_walt | calc.walt@1 |
| Net present value | calc_npv | calc.npv@1 |
| Internal rate of return | calc_irr | calc.irr@2 |
| Lease vs. own | calc_lease_vs_own | calc.lease_vs_own@2 |
| Renew vs. relocate | calc_renew_vs_relocate | calc.renew_vs_relocate@2 |
| Hotel operating metrics (USALI) | calc_hotel_metrics | calc.hotel_metrics@1 |
| Property DCF from a rent roll | calc_dcf_pro_forma | calc.dcf_pro_forma@2 |
| Direct capitalization value and implied cap rate | calc_direct_cap | calc.direct_cap@1 |
| Loan amortization schedule | calc_amortization_schedule | calc.amortization_schedule@1 |
| LP/GP equity distribution waterfall | calc_equity_waterfall | calc.equity_waterfall@1 |
| 1031 exchange deadlines, identification, and boot | calc_exchange_1031 | calc.exchange_1031@2 |
| Lease critical dates | calc_critical_dates | calc.critical_dates@1 |
| Tie out a DCF against another system's annual lines | calc_reconcile_dcf | calc.reconcile_dcf@1 |
| Tie out CAM reconciliations against another system's results | calc_reconcile_cam | calc.reconcile_cam@1 |
| Texas unequal appraisal: median of adjusted comparables | calc_tx_unequal_appraisal | calc.tx_unequal_appraisal@1 |