Finance & Investing
Annuity Future Value
FV = PMT · ((1+r)ⁿ − 1) / r
Future value of a uniform series of payments at a given rate over n periods.
Calculate →Annuity Present Value
PV = PMT · (1 − (1+r)⁻ⁿ) / r
Present value of a uniform series of payments at a given discount rate.
Calculate →Bank Discounts
D = S · d · t · Proceeds = S − D
Bank discount, proceeds, and maturity value for short-term promissory notes.
Calculate →Break Even Ratio
BER = (OE + DS) / GOI
Operating expense plus debt service as a fraction of gross operating income.
Calculate →Capital Recovery
CRF = i(1+i)ⁿ / ((1+i)ⁿ − 1)
Annual payment that recovers a present-day capital cost at a given interest rate.
Calculate →Cash on Cash Rate
CoC = Annual Cash Flow / Cash Invested
Pre-tax cash return as a fraction of cash invested in an income property.
Calculate →Compound Interest
A = P · (1 + r/n)^(n·t)
Future value with annual, semi-annual, quarterly, monthly, daily, or continuous compounding.
Calculate →Compounding and Discount Factors
(P/F · F/P · A/P · P/A · A/F · F/A)
Six standard engineering-economics factors for time-value-of-money conversions.
Calculate →Uniform Gradient
P = G · [(1+i)ⁿ − i·n − 1] / (i² · (1+i)ⁿ)
Present and future worth of a linearly-increasing series of payments.
Calculate →Depreciation
D = (Cost − Salvage) / Life
Choose between straight-line, double-declining, sum-of-years, and constant-percentage methods.
Calculate →Straight Line Depreciation
D = (Cost − Salvage) / Life
Equal annual depreciation over an asset's useful life.
Calculate →Double Declining Depreciation
D = 2 / Life · Book Value
Accelerated depreciation at twice the straight-line rate.
Calculate →Sum of Years Depreciation
D = (Remaining / SOYD) · Depreciable
Accelerated depreciation weighted by sum-of-the-years' digits.
Calculate →Future Value
FV = PV · (1 + r)ⁿ
Future value of a single present-day cash flow at a given interest rate.
Calculate →Gross Domestic Product
GDP = C + I + G + (X − M)
GDP from consumption, investment, government spending, and net exports.
Calculate →Inflation Rate
i = (CPI_new − CPI_old) / CPI_old
Period-over-period inflation rate from a price index series.
Calculate →Interest Rate
r from PV, FV, n
Periodic interest rate implied by a present value, future value, and time horizon.
Calculate →IRR
0 = Σ CF_t / (1 + IRR)^t
Internal rate of return — the discount rate that zeroes NPV for a cash-flow series.
Calculate →Loan
M = P · r · (1+r)ⁿ / ((1+r)ⁿ − 1)
Monthly payment, total interest, and amortization for an installment loan.
Calculate →NPV
NPV = Σ CF_t / (1 + r)^t − C₀
Net present value of a series of future cash flows at a chosen discount rate.
Calculate →Present Value
PV = FV / (1 + r)ⁿ
Present value of a single future cash flow at a given discount rate.
Calculate →Present Worth Analysis
PW = Σ CF · (P/F, i, t)
Present worth of any combination of present, single-future, and uniform-series cash flows.
Calculate →Profitability Index
PI = PV of inflows / Initial investment
Profitability index for capital-budgeting decisions — accept when PI ≥ 1.
Calculate →Return on Equity
ROE = Net Income / Equity
Profitability ratio measuring return on shareholders' equity.
Calculate →Rule Of 72
Years ≈ 72 / r%
Approximate doubling time for an investment at a given annual rate.
Calculate →Sales Tax
Total = Price · (1 + tax%)
Final price after sales tax and the implied tax amount.
Calculate →Sinking Fund
A = F · i / ((1+i)ⁿ − 1)
Required periodic deposit to accumulate a target future amount.
Calculate →Finance and investing calculators covering loan amortization, compound interest, NPV/IRR/payback investment analysis, annuity present and future value, sinking funds, capital recovery factor, bank discounts, three depreciation methods (straight-line, double-declining, sum-of-years), and economic indicators (GDP, inflation rate, sales tax).
Engineering economics calcs (uniform-series present worth, uniform gradient, capital recovery factor) follow standard textbook formulas used in FE and PE exam prep.
When to use these calculators
Use the Loan and Compound Interest calculators for personal finance — monthly payments, total interest, future-value projections. Use NPV/IRR for capital-budgeting decisions. Use the Annuity calculators (Present Value, Future Value) for retirement planning or bond pricing. Use the engineering-economics calcs (Capital Recovery, Uniform Gradient, Present Worth) for cost-comparison studies.
These are educational tools — consult a CPA or financial advisor for actual financial planning.
Frequently Asked Questions
- What's the difference between NPV and IRR?
- NPV (Net Present Value) is the dollar value today of a stream of future cash flows discounted at a chosen rate; positive NPV means the project beats the discount rate. IRR (Internal Rate of Return) is the discount rate at which NPV equals zero — the project's break-even return. NPV is preferred for absolute value; IRR for project ranking.
- How is compound interest different from simple interest?
- Simple interest computes interest only on the original principal each period. Compound interest reinvests interest earned into the principal so the next period earns interest on a larger base. The Compound Interest calculator supports annual, semi-annual, quarterly, monthly, daily, and continuous compounding.
- What's the capital recovery factor used for?
- Capital recovery factor (CRF) converts a present-day lump sum into an equivalent uniform annual payment, given an interest rate and time horizon. Engineers use it to spread a large initial capital cost over the life of a project for annual cost-comparison.