Percentage calculator
What is X% of Y, X is what percent of Y, and percentage increase or decrease — the three questions behind most 'quick maths' searches.
result = value × percent ÷ 100
Home/Business Calculators
// Free tools
Eight business calculators, no signup, no tracking
Percentage, discount, margin and markup, break-even, ROI and ROAS, customer lifetime value, loan instalment and compound interest — the calculations that come up most often in running a shop. Everything runs in your browser; nothing is sent anywhere.
Discount & sale price
Take a list price and a discount and get the sale price, the money saved and the effective margin hit. The number every promotion decision starts from.
sale = list × (1 − discount ÷ 100)
Profit margin & markup
The two numbers that get confused most often, and the confusion is expensive. A 50% markup is a 33% margin — price on markup when you meant margin and you have quietly given away a third of your profit.
margin % = (price − cost) ÷ price × 100 · markup % = (price − cost) ÷ cost × 100
Break-even point
How many units you must sell before you stop losing money. Fixed costs divided by the contribution each unit makes — the sanity check before any product launch.
units = fixed costs ÷ (price − variable cost)
ROI & ROAS
Return on investment and return on ad spend. ROAS tells you whether a campaign made revenue; ROI tells you whether it made money. They are not the same, and only one pays salaries.
ROI % = (gain − cost) ÷ cost × 100 · ROAS = revenue ÷ ad spend
Customer lifetime value
What a customer is worth over the whole relationship. In B2B this is the number that justifies your acquisition cost — and it is almost always higher than people assume.
CLV = order value × orders per year × years × margin %
Loan / instalment (EMI)
The monthly payment on a loan or a financed investment, plus what it costs you in interest over the term. Useful before signing for that new warehouse system.
EMI = P × r × (1+r)ⁿ ÷ ((1+r)ⁿ − 1)
Compound interest
What an amount grows to when the return compounds. The same maths behind savings, inflation and why a 2% monthly growth rate is a very different number after a year than people expect.
A = P × (1 + r ÷ n)^(n × t)
// The one that costs money
Margin is not markup — and the difference is a third of your profit
If a product costs you 60 and you want to "make 50%", which 50% do you mean? Add 50% to the cost and you sell at 90 — that is a 33% margin, not 50%. To actually make a 50% margin you must sell at 120. Every year we find shops that have priced an entire catalogue on the wrong one.
| Cost | Markup | Selling price | Actual margin |
|---|---|---|---|
| 60 | 25% | 75 | 20% |
| 60 | 50% | 90 | 33% |
| 60 | 100% | 120 | 50% |
| 60 | 150% | 150 | 60% |
// FAQ
About these calculators
Margin is profit as a percentage of the selling price; markup is profit as a percentage of the cost price. A 50% markup on a 60 cost gives a 90 price — which is only a 33% margin. Confusing the two is one of the most common and most expensive pricing mistakes in e-commerce.
It depends entirely on your margin. At a 20% gross margin, a ROAS of 4 loses money: €4 of revenue carries only €0.80 of gross profit against €1 of ad spend. That is why this calculator asks for your margin and shows the real ROI as well as the ROAS.
No. Everything runs in your browser. Nothing is sent to a server, nothing is stored, and there is no tracking on the results — you can check that in the page source.
Yes — product configurators, price and quantity calculators, financing calculators and ROI tools are a regular part of our work. In a B2B shop, a calculator that answers the buyer's real question is often a stronger conversion lever than any redesign.
Need a calculator inside your shop?
Configurators, price and financing calculators, ROI tools — built into Shopware or as a standalone app.