💼 Business Calculators
All 15 free business calculators in one place — Run the numbers with 15 free business calculators — Break-Even Point, LLC vs S-Corp Tax Savings, Amazon FBA Fees, and Startup Runway tools for founders, freelancers, and sellers.. Every tool runs 100% client-side in your browser: no sign-up, no uploads, instant answers.
Last updated: September 2026 · 15 free tools
The Complete Guide to Business Calculators
Every business decision is a numbers decision — whether an idea can make money, what each customer is worth, how long the cash lasts, and which platform takes the smallest bite. This hub collects 15 free business calculators for founders, freelancers, and e-commerce sellers. Validate ideas, master your unit economics, choose the right structure, and price your products to survive fees — all instantly, all in your browser, with your numbers never leaving your device.
Prove the idea: break-even and unit economics
Start with the Business Break-Even Point calculator: how many units must you sell, at what price, to cover fixed and variable costs? That single number separates viable ideas from expensive hobbies. Then learn your unit economics — the math investors interrogate first. The CAC to LTV Ratio and Customer LTV calculators show what a customer is worth versus what they cost to acquire (a 3:1 LTV-to-CAC ratio is the commonly cited healthy benchmark), while SaaS MRR and SaaS Churn track recurring revenue and the leaks draining it. The Startup Runway Calculator converts your cash balance and burn rate into months of survival — the number every founder should know cold. Round out pricing discipline with Markup vs Margin (they are not the same thing) and the Invoice Factoring calculator for cash-flow crunches.
Choose the right structure
Entity choice has real tax consequences. The LLC vs S-Corp Tax Savings calculator compares the two structures side by side so you can see at what profit level an S-corp election starts paying for itself — then confirm the decision with a CPA, because payroll and compliance costs matter too.
Sell without surrendering your margin
Marketplace fees are silent profit killers. The Amazon FBA Fee Calculator exposes referral, fulfillment, and storage fees before you list; Shopify Fee & Margin, eBay Seller Fee & Profit, and Etsy Seller Fee & Profit do the same for their platforms; the Multi-Platform Profit Comparator lines them up so you can see where a product earns most; and the Stripe Fee Calculator shows the true net on every card transaction. Price with fees baked in — not discovered later.
How to pick the right tool
Validating an idea: Break-Even first. Scaling: CAC/LTV, churn, MRR, and runway — in that order. Choosing a structure: LLC vs S-Corp (with a CPA’s sign-off). Selling online: the fee calculators plus the profit comparator before you set prices. Everything here is free for commercial use and runs 100% client-side.
💼 All 15 Business Calculators
Every tool below is free, unlimited, and runs entirely in your browser — pick the one that matches your question.
Calculate net profit margins after Amazon referral fees, FBA pick-and-pack, and monthly warehouse storage.
Calculate minimum sales volume and dollar revenue required to cover fixed overhead and variable costs.
Calculate Customer Acquisition Cost (CAC), Customer Lifetime Value (LTV), and LTV:CAC ratios to benchmark startup unit economics and marketing sustainability.
Estimate lifetime value from average revenue, margin, and retention.
Compute net profits after eBay category Final Value Fees, listing upgrades, and Promoted Listings ad costs.
Compare net profit margins across Amazon FBA, Shopify, eBay, and Etsy for the exact same product SKU.
Calculate take-home profit after Etsy's $0.20 listing fee, 6.5% transaction cut, and payment processing.
Calculate true net hourly profit after subtracting gas, vehicle depreciation, and the standard IRS mileage rate.
Calculate the effective annual cost of receivables factoring fees and early vendor payment discounts (e.g. 2/10 Net 30 annualized APR).
Calculate how much federal self-employment tax (15.3% FICA) an LLC owner can save by electing S-Corporation status and splitting profits into W-2 salary vs distributions.
Measure customer and revenue churn to spot retention problems early.
Track monthly recurring revenue from plans, seats, and pricing tiers.
Model net margins after Basic, Shopify, or Advanced plans, credit card processing, and paid customer acquisition.
See how many months of cash remain at your current burn rate.
Compute Stripe processing fees and net payout on every transaction.
Business Calculator FAQs
Straight answers to the questions people ask most about business calculators.
How do I know if my business idea is financially viable?
Run a break-even analysis: if the number of units you must sell each month to cover costs is wildly beyond what the market can plausibly deliver, the idea needs reworking — price, costs, or both. The Business Break-Even Point calculator gives you that number in seconds, before you spend a dollar.
What is a healthy LTV-to-CAC ratio?
The commonly cited benchmark is 3:1 — a customer’s lifetime value should be roughly three times what you paid to acquire them. Below that, growth can destroy value; far above it, you may be under-investing in growth. The CAC to LTV Ratio and Customer LTV calculators show exactly where you stand.
LLC or S-corp — which saves more on taxes?
It depends on profit level. An LLC is simpler; an S-corp election can reduce self-employment tax once profits are high enough to justify a reasonable salary plus payroll overhead. The LLC vs S-Corp Tax Savings calculator models the crossover point — then have a CPA validate it for your state and situation.
How much runway does my startup need?
Divide cash on hand by monthly burn: that is your runway in months. Many advisors suggest raising or reaching profitability with 12–18+ months of runway as a cushion, since fundraising takes months. The Startup Runway Calculator makes the math instant — and brutally honest.
Which marketplace fees eat the most margin?
It varies by product price, size, and category — Amazon FBA, Shopify, eBay, Etsy, and Stripe all take their cut differently. Rather than guessing, run your product through the Multi-Platform Profit Comparator and the individual fee calculators to see net profit per platform before you commit inventory.
Are these business calculators free for commercial use?
Yes. All 15 are free with no sign-up and no limits, and they run entirely in your browser — your revenue figures, costs, and margins are never uploaded anywhere.