Interactive finance tools you can drag
- Tools you can drag
- 67
- Calculators
- 132
- Guides
- 216
- Worked examples
- 1,307
Things you can drag. Each one runs in your browser, works on a phone, and is free to embed on your own site with a link back. An AI assistant can quote a formula. It cannot drag a rate.
Start by dragging something
- Debt payoff simulatorSnowball or avalanche
- Yield curve explorerDrag the curve
- Allocation glide pathDrag the mix
- Rent against buyDrag the stay
- Fee drag explorerDrag the fee
- Sequence of returnsDrag the order
- Inflation eroderDrag the years
- Extra payment explorerDrag the extra
- Employer match explorerDrag the deferral
- Diversification simulatorDrag the mix
- Lump sum against averagingDrag the split
- FIRE number explorerDrag the rate
- Amortisation explorerDrag the term
- Budget allocation explorerDrag the split
- Present value explorerDrag the wait
- APR against APY explorerDrag the compounding
- Risk and return explorerDrag the mix
- Retirement projectionDrag the withdrawal
- Marginal tax explorerDrag the income
- CAGR explorerDrag the finish
- Debt-to-income explorerDrag the debts
- P/E ratio explorerDrag the earnings
- WACC explorerDrag the debt mix
- NPV explorerDrag the rate
- Operating leverage explorerDrag units
- DCF explorerDrag terminal growth
Want the graph on a class page? Copy an iframe from widgets or the embed graphs catalog. Steps for Google Sites and Canvas are on the teachers page.
Growth and time
Compound growth curve you can drag
Drag the balance curve to set the annual return and watch the gap open between the money you paid in and the interest that compounding added on top.
CAGR: drag the ending value
Drag the ending value of a holding and watch the compound annual growth rate move. Same start, same finish, half the years, and the rate more than doubles.
Real return: drag inflation
Drag inflation against a quoted return and watch the real rate, and the two balances, pull apart. Subtracting inflation overstates the gain whenever the return beats prices.
Rule of 72: drag the rate
Drag the annual rate and watch the rule-of-72 doubling time sit next to the exact logarithm. The shortcut is sharpest near 8 percent and runs short at high rates.
Ordinary vs due: drag the years
Two ending balances from the same monthly payment: ordinary (end of month) against due (start of month). The gap is always one period of growth, for any horizon.
APR against APY you can drag
Drag the quoted APR and watch the effective yield pull away as compounding is added. At card rates the gap is whole percentage points. At savings rates it is a few tenths.
Savings goal: drag the deadline
Drag the years to a savings target and watch the monthly deposit fall. Same target, same rate, more years, and most of the cut is extra deposits, not extra interest.
Present value: drag the wait
Drag the years until a future lump is due and watch today's value shrink. Same lump, same rate, a longer wait, and more growth is being undone.
Simple interest: drag the years
Drag the term and watch simple interest add the same slice every year. The line is straight because the rate never sees interest already paid.
How your savings rate sets the timeline
Drag the savings rate and watch the years of saving fall. The curve is steep at low rates, so the first few points added are worth far more than the last few.
What inflation does to buying power
Drag an inflation rate and a savings rate to watch buying power fall. Shows the share of today's buying power left each year and how long it takes to lose half.
What a yearly fee costs over decades
Drag the fee up and watch two growth curves separate. A 1 percent yearly fee is not a 1 percent cost: over 30 years it takes close to a fifth of the ending balance.
Invest all at once or spread it out?
Drag the market trend and the buying window to see which path finishes ahead. A rising market favours investing at once, a falling one favours spreading the same sum.
Why the order of returns matters
Drag ten fixed yearly returns from worst first to best first. Take nothing out and the ending balance never moves. Take a fixed sum out and the order decides it.
Debt
Debt snowball vs avalanche simulator
Drag the total monthly payment and compare two payoff curves, highest rate first against smallest balance first. Shows months to debt free and what each order costs.
Extra payment curve you can drag
Drag extra monthly principal on a fixed loan and watch months remaining and interest saved. The curve flattens: the first extra dollars cut more time than the later ones.
Amortisation explorer: drag the rate
Drag a rate up or down and watch every loan payment split into interest and principal. Marks the payment where principal first overtakes interest.
Credit utilization: drag the balance
Drag a reported balance against a total credit limit to see utilisation as a percentage and the band it falls in, with the direction of effect rather than a score.
Debt-to-income: drag the debts
Drag monthly debt payments against gross income and watch the ratio eat a 36 or 43 percent ceiling. Room left is the figure a new loan has to fit inside.
Card payoff: drag the payment
Drag the monthly payment on a revolving balance and watch the term collapse, or hit the interest line where the debt never clears. Extra dollars go straight to principal.
PMI: drag the down payment
Hold the home price still and drag the down payment. Months of PMI fall as loan-to-value falls, and at 20 percent down the rider is already off.
Affordability: drag other debts
Hold gross pay, tax, insurance and the rate still and drag other monthly debts. The loan ceiling falls because the back-end room for principal and interest shrinks.
Investing
Risk against return scatter plot
Drag a portfolio point along the curve between two assets and watch expected return move in a straight line while risk does not. Illustrative teaching values, plotted.
How diversification cuts portfolio risk
Drag the correlation and the number of holdings to watch portfolio risk fall towards a floor. Shows the risk diversification removes and the shared risk it cannot.
How a stock and bond mix shifts with age
Drag a glide path to see stock and bond shares change with age, read the mix at any age, and watch an illustrative risk level move with it.
Bond price against the market rate
Drag along the price-yield curve to set the market rate and watch the bond price move the other way. Par, premium and discount are marked, and longer maturity tips the curve steeper.
Yield curve shapes: drag the curve
Drag a control point at each maturity to build a yield curve and see it named normal, flat, inverted or humped, with what each shape is usually read as.
Break-even: drag the price
Drag the selling price and watch the break-even count fall. Each extra unit of price goes straight into the contribution margin, which cuts the units needed hard.
Leverage ratios you can drag
Drag the debt share of one balance sheet and watch debt-to-equity, debt-to-assets and the equity multiplier move together. They are three readings of one fact.
P/E ratio: drag the earnings
Hold the share price still and drag earnings per share. The multiple falls when the year gets more profitable, which is why a lower P/E is not always a cheaper share.
Cap rate: drag the price
Hold net operating income still and drag the purchase price. A higher price is a lower cap. The comparison cap turns that yield into an implied value.
Coverage: drag EBIT
Hold the interest bill still and drag EBIT. Coverage is a multiple, not a percent. Halve operating profit and the multiple halves, with no new borrowing required.
Cash cycle: drag payables
Hold receivables and inventory days still and drag payable days. The cash conversion cycle is the residual the firm still has to fund. Stretch DPO far enough and it turns negative.
WACC: drag the debt mix
Hold the two input costs still and drag how much of the capital is debt. WACC slides toward the after-tax cost of debt. Holding those costs fixed is the trick in the fall.
ROE: drag net income
Hold book equity still and drag net income. ROE is profit after interest over the residual claim. The same 15 percent on ROIC is a different object, because financial leverage sits inside ROE.
Tax-equivalent yield: drag the band
Hold a tax-exempt yield still and drag the federal marginal rate. The equivalent is the taxable yield that matches after tax. Lower bands shrink the gap.
Enterprise value: drag cash
Hold equity and debt still and drag surplus cash. Enterprise value is equity plus net debt. Cash you could hand back comes off EV one for one, and the multiple moves with it.
Offer premium: drag the bid
Hold the unaffected close still and drag the offer price. Premium is the bid over that close, not over the last trade after the rumour is in the tape.
NPV: drag the discount rate
Hold a five-year series still and drag the discount rate. NPV falls as the rate rises, and it crosses zero at this series IRR.
IRR: drag the annual receipt
Hold the outlay still and drag the annual receipt on a five-year series. IRR is the rate that drives NPV to zero, so a fatter receipt is a higher rate.
Payback: drag the annual cash
Hold the outlay still and drag the annual cash a project returns. Payback is the date the running total hits the cost, and it ignores everything after that date.
DCF: drag terminal growth
Hold five flat years of cash and WACC still and drag terminal growth. Most of enterprise value sits in the terminal stage, which is why g moves the answer so hard.
Free cash flow: drag capex
Hold EBIT, tax, D and A and working capital still and drag capex. Unlevered free cash flow falls one for one with the capex line. EBITDA does not move.
ROIC: drag invested capital
Hold NOPAT still and drag invested capital. ROIC falls when the denominator rises, which is a heavier capital stock, not a worse year of profit.
Gordon growth: drag the growth rate
Hold the dividend and the required return still and drag perpetual growth. The Gordon price is next year's dividend over required return minus growth.
Duration: drag the maturity
Hold a 5 percent par bond still and drag years to maturity. Macaulay duration stays shorter than maturity because coupons arrive first, and DV01 is the dollar sensitivity.
Unlevered beta: drag D/E
Hold equity beta and the tax rate still and drag debt-to-equity. Asset beta falls as the Hamada factor rises, because more of the equity beta was financing.
Working capital: drag current assets
Hold current liabilities still and drag current assets. Working capital is the dollar gap. The current ratio is the same comparison as a division.
Operating leverage: drag volume
Hold price, variable cost and fixed costs still and drag units. Degree of operating leverage is contribution over EBIT, and it is largest just above break-even.
ROA: drag net income
Hold total assets still and drag net income. ROA is profit after interest over the whole balance sheet. Times the equity multiplier, that rate is ROE on the same sheet.
DuPont: drag net income
Hold sales, assets and equity still and drag net income. Margin moves, turnover and the equity multiplier do not, and ROE is the product of the three.
DFL: drag EBIT
Hold the interest bill still and drag EBIT. Degree of financial leverage falls toward 1 as coverage rises, and blows up as EBIT approaches the coupon.
PEG: drag expected growth
Hold P/E still and drag expected EPS growth. PEG is the multiple over the growth points. Growth of 10 means ten percent, so a P/E of 20 is a PEG of 2.
P/B: drag book value
Hold the share price still and drag book value per share. P/B is price over BVPS, which is market cap over book equity. Raise book and the multiple falls.
Operating margin: drag EBIT
Hold sales still and drag EBIT. Operating margin is EBIT over sales. D&A stays put, so EBITDA margin moves with EBIT but not one-for-one.
Total return: drag the finish
Hold the start and the income still and drag the ending value. Total return is price change plus income, over the start. A flat finish is a pure income return.
P/S: drag sales per share
Hold the share price still and drag sales per share. P/S is price over SPS, which is market cap over sales. Raise sales and the multiple falls.
FCF yield: drag market cap
Hold free cash flow still and drag market cap. FCF yield is unlevered cash over the equity cap. A smaller cap on the same cash is a higher yield, not a fatter cheque.
Cash ratio: drag the cash
Hold current liabilities still and drag cash. The cash ratio is cash over the bills due within a year. Raise cash and coverage rises. Receivables and inventory stay out.
Household planning
Budget allocation explorer
Drag five spending bands to see where take-home pay goes. Each band is a share of take-home, the five plus the unassigned remainder always total 100 percent, and the saving rate is the headline.
Rent against buy: the break-even year
Drag the horizon and watch rent paid so far meet the cost of owning, counting interest, tax, upkeep and the cost of buying and selling. Illustrative figures.
Retirement projection you can drag
Drag the monthly contribution and the expected return, and watch a retirement balance redraw with a fan showing the same plan 2 points either side of your rate.
Employer match curve you can drag
Drag the share of pay you defer and watch the employer match rise until the cap, then go flat. Past the cap, extra deferral is your money alone.
Marginal against effective tax rate
Drag an income marker across illustrative tax bands to see the rate on the next dollar, the effective rate on the whole income, and why a raise still lifts take-home pay.
Net worth: drag the debts
Hold assets still and drag debts. Net worth is the remainder on one date. Past the assets mark the residual is negative, which is arithmetic, not a verdict.
Hourly wage: drag the hours
Hold the hourly wage still and drag hours a week. Annual pay is wage times hours times weeks. Four weeks of weekly pay is not a month of a 52-week year.
FIRE number: drag the rate
Hold annual spending still and drag the withdrawal rate. The pile is spending over that rate. A 4 percent rule is 25 times spending. A 3 percent rule is about 33 times.