Tools & Calculators
Run the numbers yourself
101 working calculators, scorecards, and upload-and-go file tools. Every result computes live, every formula is shown, and file tools run entirely in your browser (nothing is ever uploaded). Each one is paired with the lessons that explain the thinking.
- A/B Test Sample Size Calculator — The number that decides whether a test is worth running at all. Most teams pick a two-week window and read whatever they see; this works the other way round — you say what size of improvement would actually change a decision, and the maths tells you how many people it takes to see it, and how many weeks of your traffic that is. Very often the honest answer is that you cannot detect the lift you are hoping for, and knowing that before you start is worth more than the test.
- Ad Cost per Order Calculator — What one paid order really costs you once ads, fulfillment, and payment fees are all counted — the number a screenshot of your ad dashboard hides.
- Ad Metrics (CTR / CPC / CPM / CPA) Calculator — Turns raw campaign numbers into the four rates every ad platform reports — CTR, CPC, CPM, and CPA — so you can compare campaigns on the same footing.
- AI vs Human Task Cost Calculator — Human versus AI cost for a repetitive task — the per-task arithmetic behind every "should we automate this?" debate.
- Asset Depreciation Calculator — What an asset silently costs you every month as it wears out — the expense no invoice ever shows.
- Automation Payback Calculator — Whether an automation or AI tool pays for itself — hours saved priced at what your time actually costs.
- Break-Even CAC Calculator — The most you can pay to acquire a customer before the relationship stops making money — the ceiling for every ad budget.
- Break-Even Point Calculator — How many units — and how much revenue — you must sell each month just to cover fixed costs and reach $0. Everything above is profit.
- Break-Even ROAS Calculator — The return on ad spend where you stop losing money — below this ROAS, growth is just expensive shrinking.
- Bundle Economics Calculator — Whether a bundle discount grows profit or just gives margin away — the math behind "3 for the price of 2.5".
- Burn Multiple Calculator — How much cash you burn for every $1 of new recurring revenue you add. The lower the number, the more efficient your growth.
- Business Acquisition Valuation Calculator — A defensible price range for a small business, built from what it actually earns its owner.
- CAC Payback Period Calculator — How many months of a customer’s margin it takes to earn back what you spent to acquire them. Shorter payback means faster, safer growth.
- CAGR & Compound Growth Calculator — The single yearly growth rate (CAGR) that turns your starting number into your ending number — the honest way to describe multi-year growth.
- Cap Rate Calculator — The yield a property earns regardless of how you finance it — the cleanest way to compare deals.
- Cap Table Dilution Calculator — What your ownership becomes after the new round and option pool — before you celebrate the valuation.
- Cash Conversion Cycle Calculator — How many days your cash is trapped between paying suppliers and getting paid — negative numbers mean customers fund your growth.
- Cash Reserve Calculator — The cash cushion that lets your business survive a bad quarter without panic decisions.
- Cash Runway Calculator — How many months until the cash runs out at your current burn — the single most important number for a business that isn’t yet profitable.
- Cash-on-Cash Return Calculator — The return on the cash you actually put in — what leverage does to (and for) your yield.
- Center of Gravity (Facility Location) Calculator — Where to put the warehouse. Plot the places you ship to on any grid, weight each by how much moves there, and the centre of gravity is the point that balances them — the classic first answer to a distribution-centre question, and the one that stops an argument about which city "feels central" from being settled by whoever is loudest.
- Churn & Retention Calculator — Translates a monthly churn rate into the two numbers that matter: how long the average customer stays, and what they’re worth over that lifetime.
- Comparable Company Multiples Calculator — What the market pays for businesses like this one, discounted for the fact that yours is smaller and harder to sell. The useful part is not the answer — it is seeing how far apart the three comparables already are before any discount is applied.
- Contribution Margin Calculator — How many dollars each unit actually contributes toward fixed costs and profit after every variable cost is paid.
- Conversion Rate & Revenue Calculator — Turns traffic into a revenue forecast: how many visitors, converting at what rate, at what order value — and what one extra point of conversion is worth.
- Cost of a Bad Hire Calculator — What a hire that did not work out actually cost, counted line by line instead of quoted as a multiple. The number people repeat in a room is a gross figure — everything spent from the first job ad to the replacement being productive. The number that should decide anything is the incremental one: what you spent that a hire who worked out would not have cost you. This shows both, and it prices the piece every estimate leaves out, which is your own hours and your team's.
- Covenant Headroom Calculator — One number matters here: how far EBITDA can fall before you trip. Everyone knows their leverage ratio today. Almost nobody knows the drop that breaches it — which is the number that decides whether a soft quarter is an inconvenience or a call with the lender.
- Customer Lifetime Value Calculator — What one customer is worth in margin dollars over the whole relationship — the number that decides how much you can spend to win them.
- DCF & Terminal Value Calculator — Two terminal values side by side, because that is where a DCF is actually decided. The explicit forecast is arithmetic; the terminal value is a guess, and it is usually most of the answer. This shows how much of the enterprise value sits beyond the forecast — and what each terminal method implies about the other.
- Debt Schedule with Revolver — The circularity every simple LBO model skips. Interest depends on the debt balance, the balance depends on how much cash is left after interest, and the cash sweep depends on both. This walks one year of it properly: EBITDA down to cash for debt service, mandatory amortisation, then a sweep against the term loan — or a revolver draw if the year comes up short.
- Debt Service Calculator — Whether the business's cash flow can actually carry the loan — the coverage ratio every lender checks first.
- Decision Tree & Expected Value Calculator — Two options, three ways the world could go. The tool weights every branch by its probability, nets off what each option costs to take, and shows not just which one wins on expected value but what you would lose by picking the other one — and how bad each choice looks if the world goes against you.
- Discount Break-Even Calculator — How much extra volume a discount must generate just to break even — the math most "SALE" signs never did.
- Distribution Waterfall & Carry Calculator — Where the money in a fund or a syndicated deal actually goes, tier by tier. Capital back first, then the preferred return, then the sponsor catches up, then everything left is split. The headline carry number on the term sheet is almost never the share the sponsor ends up with, and this shows you the gap.
- DSCR (Debt Coverage) Calculator — Whether a property’s income covers its loan payments — the ratio lenders check first. Below 1.0 means the property can’t pay its own mortgage.
- Due Diligence Scorecard — Where a deal stands on the checks that matter — and how hard the open red flags should pull on your enthusiasm.
- Economic Order Quantity (EOQ) Calculator — The order size that minimizes total inventory cost by balancing the cost of ordering against the cost of holding stock — the classic economic order quantity.
- Email Campaign ROI Calculator — What an email campaign actually returns once you account for click-through, conversion, and order value — usually the highest-ROI channel, and this shows why.
- Email List Cleaner — Drop any messy file of emails. It dedupes, validates, repairs common typos (gamil → gmail), and hands back a clean list ready for your email platform.
- Equipment ROI Calculator — Whether a piece of equipment earns its keep over its working life — payback, total profit, and the return multiple.
- Equity Split Calculator — A structured starting point for splitting founder equity — replacing the 50/50 handshake with actual contributions.
- Expense Categorizer — Drop a bank or card CSV and get spend auto-sorted into categories: monthly burn, the vendors eating your margin, and a categorized file to download.
- Experiment Readout Calculator — The other half of the test, and the half that goes wrong. Two conversion rates always differ; the question is whether they differ by more than chance would produce anyway. This gives you the lift, the range the true lift plausibly sits in, and a p-value — and then tells you plainly when that range includes zero, which means you learned nothing, or when the sample is too small for any of it to mean much.
- Exponential Smoothing Forecast Calculator — The forecast underneath every inventory number you will ever calculate. Exponential smoothing weights the recent past most heavily and lets the rest fade, so a single constant decides how fast your forecast reacts to a surprise. Enter your demand history, choose that constant, and this forecasts the next period, grades itself against the periods it has already seen, and says whether it is beating the dumbest rule there is: assume next month looks like this one.
- Financial Document Builder — Build your own balance sheet, income statement, cash flow statement, cap table or invoice. Totals and balance checks work as you type, and you can download it as a PDF.
- Fix & Flip 70% Rule Calculator — The most a flipper should pay for a house so there’s room for repairs, holding costs, and profit — the industry’s “70% rule,” made adjustable.
- Forecast Accuracy & Tracking Signal Calculator — Grade a forecast you already have. Put your forecast for each period beside what actually happened and this returns the four error measures an operations course asks for — MAD, MSE, RMSE and MAPE — plus the one that matters most and gets quoted least: the tracking signal, which separates a forecast that is merely imprecise from one that is wrong in the same direction every single period.
- Freelance Billable Rate Calculator — The hourly rate a freelancer or agency must charge to hit a target income, once you subtract the non-billable hours nobody pays you for.
- Freight Cost Calculator — Air versus ocean for your actual shipment — the crossover math freight forwarders do in their heads.
- Gross Margin & Markup Calculator — The share of every sales dollar left after the direct cost of making or buying the product — before rent, ads, or payroll.
- Insolvency & Runway Test — The two questions a court and a lender both ask: can you pay debts as they fall due (the cash flow test), and do your assets exceed your liabilities (the balance sheet test)? Failing either one changes who your duties run to.
- Inventory Turnover Calculator — How many times a year your inventory sells through — slow turns are cash sitting on shelves.
- Landed Cost Calculator — The real cost of getting one unit to your door — the number your margin math must start from, not the factory price.
- LBO Returns Calculator — A buyout in one page: buy at a multiple, fund part of it with debt, grow the earnings, pay the debt down, sell at a multiple. The equity return is what is left — and this shows how much of it comes from the business versus the leverage.
- Lease Versus Buy Calculator — The total-cost showdown between leasing and buying over your actual holding period — not the salesman's version.
- LTV:CAC Ratio Calculator — Whether each customer is worth what you pay to get them. The rule of thumb: earn at least 3× what acquisition costs.
- Market Sizing (TAM/SAM/SOM) Calculator — A top-down TAM/SAM/SOM estimate in four inputs — enough rigor to sanity-check an idea in five minutes.
- Market Tipping Calculator — Whether a share lead compounds or decays. In a market with network effects, share is an input to quality: every user makes the product better for the next one, so a lead can feed itself until one firm holds nearly everything — or it can sit at a stable split forever. Which of those happens is decided by a handful of parameters, and the most important one is how easily users keep a foot in both camps. This finds the tipping point: the share you have to hold before the market starts doing your marketing for you.
- Marketing Funnel Calculator — Walks your traffic through the funnel — visitors to leads to customers to revenue — and shows which stage is leaking the most.
- Marketplace Fee Calculator — What's actually left after the marketplace takes its cuts — the number to know before you price.
- Marketplace Take-Rate Designer — What a platform can safely tax. A take rate is not a price — it is a tax on transactions someone else could, in principle, do without you, and its ceiling is set by the seller's alternative rather than by your costs or your ambitions. This puts the two numbers that actually bind side by side: the rate above which a rational seller starts going direct, and the rate that maximises your revenue this quarter. They are not the same number, and the gap between them is where most platform self-harm happens.
- Markup ↔ Margin Converter — The number people mix up most: a 50% markup is only a 33% margin. Enter the margin you actually want and see the markup and price it takes.
- Monte Carlo Outcome Simulator — A single-point forecast tells you one story. This runs four thousand versions of the year — revenue and variable cost drawn independently around the averages you enter — and reports how often you hit the target, how often you lose money, and what a bad year and a good year actually look like.
- Mortgage Payment Calculator — The monthly principal-and-interest payment on a loan, plus the total interest you’ll pay over its life — often more than the amount borrowed.
- MRR / ARR Growth Calculator — Projects recurring revenue forward: turn today’s MRR into ARR, then compound your monthly growth to see where you land in a year.
- Negotiation Range (ZOPA) Calculator — Map the deal space before you walk in: where agreement is possible, and where your opening number should sit.
- Net Profit Margin Calculator — The bottom line: what’s left of each sales dollar after everything — goods, overhead, and operating costs — is paid.
- Newsvendor Order Quantity Calculator — How much to order when you get exactly one shot and demand is uncertain — the Christmas tree, the printed programme, the perishable batch, the launch run. The instinct is to order the average, and the average is almost always the wrong answer. What decides it is the ratio between what a stockout costs you and what a leftover costs you; when they are not equal, the right order quantity is not the mean.
- NPV, IRR & Payback Calculator — The four numbers a capital request gets judged on, from one set of cash flows. NPV says how much value the project adds, IRR says the rate it earns, payback says how long your money is at risk, and the profitability index says how much value you get per dollar committed when you cannot fund everything.
- Platform Risk Scorecard — How much of your business one platform policy email could erase — the dependency check every online seller needs.
- Price-to-Rent & 1% Rule Calculator — A fast screen on whether a property is priced to cash-flow. Combines the price-to-rent ratio with the investor’s “1% rule.”
- Pricing Calculator — The price your target margin actually requires once fees are loaded in — and how it sits against the competition.
- Product Image Optimizer — Drop product photos and get web-ready versions (resized, compressed up to 90% smaller, in WebP or JPEG) so listings load fast and sell.
- Production Order Quantity (EPQ) Calculator — The run length for something you MAKE rather than buy. The order quantity everyone learns assumes a delivery lands all at once; a production run does not, because you are selling out of the batch while the batch is still being made. Stock therefore peaks well below the run size, holding costs less than it looks, and the right run is longer than the order quantity would tell you.
- Profit First Allocation Calculator — Splits every dollar of revenue into profit, owner’s pay, taxes, and operating expenses before you spend it — the Profit First method, so profit is a habit, not a leftover.
- Purchase Price Allocation Calculator — After a deal closes the price has to be spread across everything you bought. Tangible assets and identified intangibles take fair value, assumed liabilities come off, a deferred tax liability is booked on the intangible step-up, and whatever is left over becomes goodwill. Goodwill is the part you cannot name — and the part that gets tested for impairment every year.
- Quantity Discount (Price Break) Calculator — Whether a price break is worth the stock it makes you hold. A supplier offers a lower unit price for a bigger order, which pulls in two directions at once: the goods cost less and every unit of the extra inventory costs you money all year. The answer is not the deepest discount, and it is not the plain order quantity either — you have to price each break as its own plan and compare the totals.
- Quarterly Estimated Tax Calculator — Roughly what to set aside for taxes from a profitable business — split into a quarterly payment and a per-week set-aside so it never becomes a surprise.
- Queue and Capacity Calculator — Why the line explodes. Capacity planning fails because waiting time does not rise in a straight line with load — it bends, and then it goes vertical. A team at 70% busy has a queue you can live with; the same team at 90% busy, doing only a fifth more work, has one you cannot. This puts numbers on that curve for a support desk, a checkout, a clinic, a service team, or anything else where arrivals meet a fixed number of servers.
- Rental Payback Calculator — How many months until a rental asset pays for itself — everything after that is the return.
- Rental Property Cash Flow Calculator — What a rental property actually puts in your pocket each month after every expense and the mortgage — the number that separates an asset from a liability.
- Rental Utilization Calculator — What share of possible rental days actually earn — the single number that makes or breaks rental businesses.
- Reorder Point & Safety Stock Calculator — The stock level that should trigger your next order, so you don’t run out during the lead time — plus how much safety stock buffers the surprises.
- Revenue Concentration Risk Calculator — How much of your business one phone call could delete — the risk hiding inside a great top customer.
- ROI Calculator — The return on any investment — a campaign, a hire, a machine — as a percentage, plus the annualized rate so you can compare across different time spans.
- Runway & Default-Alive Calculator — Months of cash left at the current burn — and Paul Graham's harder question: on your growth curve, do you reach profitability BEFORE the money runs out (default alive), or not (default dead)?
- Safety Stock & Service Level Calculator — How much stock you are holding purely to absorb being wrong, and what each extra point of service level costs to buy. The formula every operations course teaches combines two separate uncertainties — demand that moves and a supplier who is late — and it usually turns out that most of the inventory is insurance against the supplier, not the customer. That changes what you should go and fix.
- Sales CSV Analyzer — Drop any sales export (Stripe, Shopify, Square, a spreadsheet) and instantly see revenue, average order value, monthly trend, and your real top sellers.
- Scenario Planning Calculator — Your business in three futures — and whether the bad one clears your fixed-cost floor.
- Seasonal Index & Forecast Calculator — Split a demand history into the level and the shape of the year. A seasonal index says what each part of the cycle is worth against an ordinary one: 1.47 means that quarter runs 47% above average and always has. With the shape separated out you can forecast the year as one number and let the indices put it back into months, which is how almost every real demand plan is actually built.
- Seller Financing Calculator — What a seller-financed deal really costs per month — and in total — before you shake hands.
- Seller's Net Proceeds Calculator — The gap between the number in the press release and the number in your bank account. Debt comes off, advisers take their percentage, some of the price stays behind as rollover equity, some sits in escrow for a year or more, and then the government takes a share of the gain. Owners are routinely surprised by how little of a headline price is actually theirs.
- Subscription Economics Calculator — The three numbers that decide whether a subscription business works: MRR, how long subscribers stay, and what each one is worth.
- Supplier Risk Scorecard — A 0–100 read on how exposed you are to your supply base — one supplier sneezing shouldn't hospitalize you.
- Tax Reserve Calculator — How much to set aside from every month's profit so tax season is an errand, not an emergency.
- Three-Statement Tie-Out Checker — The single check that tells you a model is not lying: rebuild cash from net income, then see whether the balance sheet can actually balance. If closing cash here does not match the cash line on the balance sheet, something is wrong — and it is almost always working capital.
- True Cost of an Employee Calculator — The real cost of a hire — well above the salary once payroll taxes, benefits, software, and space are added. Budget from this number, not the offer letter.
- True Hourly Rate Calculator — What your business actually pays you per hour of your life — often a shock next to the job you left.
- Valuation Discount Calculator (Minority + Marketability) — A quarter of a company is almost never worth a quarter of the company. Two discounts sit between the two numbers — one for not controlling anything, one for not being able to sell — and they compound rather than add. This applies both, shows the arithmetic, and puts a model-based marketability figure next to the one you entered.
- WACC Calculator — The discount rate everything else in corporate finance hangs off. Cost of equity from CAPM, cost of debt after the tax shield, weighted by what each is actually worth in the market — not what the balance sheet says they cost.
- Working Capital Peg & True-Up Calculator — The adjustment that quietly moves hundreds of thousands of dollars after the handshake. The buyer expects to receive the business with a normal amount of working capital in it. Deliver more than the peg and the seller is owed money; deliver less and the seller writes a cheque back — often months after closing.