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• 50/30/20 Budget in Excel: The Formulas, and What to Do When Needs Are 64%
  How to build a 50/30/20 budget in Excel with SUMIFS and a bucket column, which income figure the rule actually uses, where debt payments belong, and why the 20 is the only number worth defending.
• Biweekly Mortgage Payments in Excel: How Much You Really Save and Where the Savings Come From
  Build a biweekly mortgage schedule in Excel, compare it to a monthly extra payment and a once-a-year extra payment on the same loan, and see why almost all of the savings come from the extra money and not from paying every two weeks.
• "Cap Rate vs Cash-on-Cash Return: Formulas, Excel, and the Leverage Test"
  Cap rate prices the property and cash-on-cash prices your deal. Here is how to calculate both in Excel, why they disagree, and the one comparison that tells you whether the mortgage helps or hurts.
• Convertible Note Conversion in Excel: Interest, Cap, Discount, and the Round Price
  How a convertible note turns into shares at a priced round, with Excel formulas for accrued interest, cap price versus discount price, and a closed-form round price when the note shares sit inside the pre-money. Two worked cases, one where the cap wins and one where the discount wins.
• Debt Snowball vs Avalanche in Excel: The Rollover Formula Most Calculators Skip
  How to build a debt payoff spreadsheet that actually rolls a paid-off debt's payment into the next one, with the ranking, cascade, and summary formulas, and a worked example showing why the no-rollover shortcut is off by years.
• How Much Should a Startup Raise? The Seed Round Sizing Formula in Excel
  Size a seed round from a month-by-month cash plan instead of a guess. A worked example shows why burn times 24 undershoots by more than half a million, and how growth and dilution change the answer.
• How to Build a DCF Model in Excel: A Step-by-Step Guide
  Build a DCF model in Excel from the 10-K up: a 5-year FCF projection, WACC with CAPM, two terminal value methods, mid-year discounting, and a bridge to price.
• How to Calculate Net Worth in Excel (and the Three Adjustments Most Trackers Skip)
  A net worth calculator you can build in Excel with one table and two SUMIFS formulas, worked on one household, plus the home, car, and 401(k) adjustments that move the answer by 15% or more and the right way to read the monthly change.
• "How to Calculate WACC in Excel from a 10-K (Step by Step)"
  Build a weighted average cost of capital in Excel from public filings. Where each input lives in a 10-K, the formulas cell by cell, and the book-weight mistake that moves a DCF by 17%.
• How to Make a Loan Amortization Schedule in Excel (PMT, IPMT, PPMT and CUMIPMT)
  Build a month-by-month loan amortization schedule in Excel with PMT and three columns of formulas, check it against IPMT, PPMT and CUMIPMT, and read the three numbers in it that matter: the crossover month, the halfway month and the cost of rounding.
• LTV to CAC Ratio Formula: How to Calculate It in Excel Without Fooling Yourself
  The LTV and CAC formulas for a SaaS startup, a worked example from a sample B2B model, and the two adjustments (fully loaded CAC and a capped lifetime) that turn a 14.7x ratio into an honest 5x.
• How Much Can I Pay for a Rental Property? The Max Offer Price Formula in Excel
  Work backward from a target DSCR, cash-on-cash return and cap rate to the highest price a rental deal can carry, with closed-form Excel formulas and a worked duplex example.
• Mortgage Extra Payment Formula in Excel: How Much Interest You Save and When You Finish
  The exact Excel formulas for a mortgage amortization schedule with extra payments, how to compute interest saved and months saved against a no-extras baseline, and the three mistakes that make most homemade payoff calculators overstate the savings.
• "The Option Pool Shuffle: How a Pre-Money Pool Changes Your Price Per Share (Excel Formula)"
  Why a term sheet that tops up the option pool in the pre-money lowers your real valuation, the closed-form Excel formula for the top-up, and a worked seed round that shows what it costs founders.
• Post-Money SAFE Conversion in Excel: The Formula That Gets the Share Count Right
  How a post-money SAFE turns into shares at a priced round, why the shortcut most cap table spreadsheets use shorts the SAFE holder, and the Excel formulas that solve it in closed form with no circular reference, with a worked seed round.
• Refinance Break-Even Formula in Excel: The Simple Version and the One That Tells the Truth
  How to calculate the break-even month on a mortgage refinance in Excel, why closing costs divided by monthly savings can mislead you in both directions, and the interest-based test that gives the same answer whatever term you choose.
• Rental Property Cash Flow Formula and Cash-on-Cash Return
  Calculate rental property cash flow from gross rent to NOI, debt service, and cash-on-cash return, with a worked duplex example and a 10-year IRR view.
• "How to Calculate IRR on a Rental Property in Excel (10-Year Hold, Worked Example)"
  A step-by-step Excel build for rental property IRR, from yearly cash flow to loan balance at sale, with the equity multiple, MIRR, and a sensitivity table that shows which assumption is really carrying the return.
• Savings Rate Formula in Excel: Pick One Definition and Track It Honestly
  How to calculate your savings rate in Excel, why the same household can land anywhere from 20% to 34% depending on the definition, and how to track it by month without the averaging mistake most spreadsheets make.
• Startup Financial Model Template: What Investors Expect
  A startup financial model template walkthrough covering driver-based forecasting, the 8 things investors check, and a worked runway and raise-sizing example.
• Startup Runway Calculator: Burn Rate Formula and a Worked Example
  How to calculate startup runway from cash, gross burn, and net burn, why the one-line formula overstates it, and how to build a month-by-month runway table that tells you the real zero-cash date.
• "Terminal Value: Gordon Growth vs Exit Multiple (and How to Reconcile Them)"
  Terminal value is usually three quarters of a DCF. Here is how both methods work in Excel, why they disagree, and the cross-check that keeps your assumption honest.
• Unlevered Free Cash Flow Formula in Excel: Three Routes to the Same Number
  The unlevered free cash flow formula built three ways in Excel, from EBIT, from net income, and from cash flow from operations, on one worked company. All three land on $259. Plus the five mistakes that move it, sized in percent.