Use the free Margin by Product Line Comparer below, right in your browser. No sign-up, no software to install, and nothing is sent to a server.
Every small business owner faces the same quiet question: after all the costs and fees, how much money does a sale really leave behind? Guessing feels fast, but it hides the truth, because a price that looks healthy can turn thin once commissions, fees, or extra costs are taken off. This free Margin by Product Line Comparer answers that question in seconds, using only the numbers you already know from your own prices and costs. Type them in, and you get a clear result you can act on, instead of a feeling you have to trust.
The tool is built for everyday shop, stall, and online sellers, not for accountants. You enter a name, a cost, and a price for each of three product lines, and it returns each line's margin and profit per sale, ranked from the highest margin to the lowest. There is no sign-up, no download, and no data sent anywhere, because every calculation runs inside your own browser. That makes it safe to try different prices and costs as often as you like, until the numbers look right for your business.
Start by typing your numbers into the boxes, using the values from your last real sale or your price list where possible. Press the Calculate button, and the result appears straight below. Change any number and press the button again to compare. Try a higher price, a lower cost, or a different rate, and watch how the result moves, so you learn which number matters most for your profit.
The maths behind it is simple, and the tool shows it plainly so you can check it by hand. Margin for each line equals price minus cost, divided by price, times 100. Profit per sale equals price minus cost. Lines are then ranked from the highest margin to the lowest, so the strongest line sits at the top. Nothing is hidden in a black box, and every figure in the result comes from the numbers you typed. If a result looks surprising, re-check the inputs first, because one mistyped zero changes everything.
Take three lines. Line A costs 60 and sells for 100, so its margin is 40 percent and its profit is 40 per sale. Line B costs 30 and sells for 50, so its margin is also 40 percent, but its profit is only 20 per sale. Line C costs 90 and sells for 100, so its margin is just 10 percent. The ranking puts A and B on top and C last, yet A earns twice the cash of B on every sale.
Now raise Line C's price to 120 with the same cost of 90. Its margin rises to 25 percent and its profit rises to 30 per sale, but it still ranks last. That tells you a price rise alone may not fix a weak line. Sometimes the honest answer is a lower cost, a different supplier, or dropping the line and giving its shelf space to a stronger one.
Read the ranking together with sales volume, because margin alone never tells the full story. A line with a 40 percent margin that sells ten units a month earns less than a line with a 25 percent margin that sells a hundred units. Use the ranking to spot where to push, where to reprice, and where to cut costs, then check units sold before you move space or stock.
The most common mistake is ranking lines by price, or by profit per sale alone, and calling that the margin ranking. A high price can hide a high cost, and a big profit per sale can hide a weak margin that collapses under a discount. Another mistake is comparing lines with different cost bases, for example one line with delivery included and another without, which makes the ranking unfair.
Run the comparison once a month with fresh costs, because supplier prices move quietly. Push the top-ranked lines in your displays and bundles, and give the bottom line one clear fix: a price rise, a cheaper input, or a smaller pack. If none of those works after a fair test, free its space for a line that earns its place.
Treat every result as an estimate, not as professional financial advice. Real sales also involve taxes, refunds, packaging, delivery, payment fees, and your own time, which this tool does not count unless you include them in your costs. Use the results to compare options and to set prices with more confidence, then check the final figures against your own accounts before you commit to a new price.
Used regularly, the Margin by Product Line Comparer becomes a quick habit before you change a price, accept a new channel, or agree a commission deal. A two-minute check today can stop a price that quietly loses money tomorrow. Bookmark the page, keep your real costs close at hand, and run the numbers every time the deal changes.
Versión en español: Comparador de Márgenes por LÃnea de Producto para Tiendas – Qué LÃnea Gana Más