How to know which products are actually profitable
Your category report says groceries run at 22% and cosmetics at 38%. Useful — and misleading. Inside every category, some products pay the rent and some quietly consume it. Profitability lives at the level of the single item on the single shelf, and finding it takes four moves: true cost, hidden costs, velocity, and the keep-or-drop decision. Here is the per-product method, with real rupees.
Margin per item, not per category
A category margin is an average, and averages hide. A ‘beverages at 18%’ shelf can hold a 4% cola selling 200 units a month next to a 40% energy drink selling six. Same category, opposite jobs — one feeds volume, the other feeds margin, and the blended number tells you neither.
The question is never ‘is this category profitable’ but ‘which items inside it earn their shelf’. That is the unit level — the SKU — and it is where every real pricing, reorder and clearance decision is made. For the bigger-picture version of margin math, see gross profit vs net profit.
The hidden costs every product carries
The purchase price is only the beginning. Before a product earns anything, it consumes:
- Delivery and transport — the share of the truck, rickshaw or courier that belongs to this item
- Packaging and bags — sachet strips, carry bags, breakage in handling
- Payment fees — card and wallet commission of 1.5–2.5% on items customers mostly buy by card
- Waste and expiry — the units that expire, break or come back as returns
- Shelf time — the rent per inch per month for the space it occupies
- Counter discounts — the Rs 20 ‘regular customer’ discount applied to this SKU every day
None of these appears on the purchase invoice; all of them come out of the same margin. A product bought at Rs 500 and sold at Rs 620 does not make Rs 120 — it makes Rs 120 minus whatever the list above took. That true per-unit figure is the margin worth tracking, and it is the same logic as calculating business profit, shrunk down to one item.
Volume beats margin — most of the time
Margin is per unit; profit is per month. A 5% item selling daily beats a 40% item selling monthly, almost every time. The rupee math: a 950g tea pack earning Rs 70 a unit and moving 90 units a month contributes Rs 6,300. An imported cereal box earning Rs 279 a unit — a 31% margin — moving four units contributes Rs 1,116. The thin-margin product earns nearly six times more.
The metric that matters is contribution: margin per unit multiplied by units sold per month. Rank your shelf by contribution and the ‘best’ products reshuffle immediately — slow premium items fall, fast staples rise.
Dead stock is negative profit
A product that does not sell is not neutral — it costs. The purchase price is locked cash, the shelf is occupied rent, and expiry converts the entire cost into a straight loss. Rs 40,000 of stock that has not moved in 90 days is not an asset worth Rs 40,000; it is Rs 40,000 of profit doing nothing, carrying the slow risk of becoming worth zero.
The fix is seeing it early — a monthly list of what has not sold in 60 days, while returning, bundling or discounting can still recover most of the cash. Inventory management software produces that slow-mover list automatically; a register produces it never.
A worked example from a real shelf
Take a 5kg atta bag. Bought at Rs 2,650, sold at Rs 2,800 — Rs 150 gross, a 5.4% margin. Add its share of delivery at Rs 20 a bag and the true margin is Rs 130, or 4.6%. Now velocity: four bags a day, roughly 120 a month. True contribution: Rs 15,600 a month from a ‘low-margin’ product.
Beside it sits an imported face wash. Bought at Rs 500, sold at Rs 850 — Rs 350 gross, a 41% margin. It sells three units a month: Rs 1,050 of contribution. And one unit expiring in a year wipes out Rs 500 — nearly half a month of everything it earned. The atta contributes fifteen times more on a margin eight times thinner. Percentages rank products; contribution pays bills.
What to do with the bottom 20%
Every shop's bottom fifth of SKUs does the same three things: occupies shelf, ties up cash, adds counting work. For each one there are exactly four moves — reprice it, bundle it with a fast mover, clear it back into cash with one deliberate discount, or drop it and give the shelf to a product that earns. The only wrong option is the fifth: leaving it there because nobody looked.
Doing this by hand means exporting sales, subtracting costs and sorting a spreadsheet nobody has time for. A profit visibility report does the ranking automatically — every product, every month, sorted by the rupees it actually contributed.
Frequently asked questions
How do I calculate the profit margin on a single product?
Selling price minus landed cost, divided by selling price, times 100. Landed cost means the purchase price plus that item's share of delivery and packaging — not just the invoice figure.
Is a low-margin product worth keeping?
Yes, if it turns fast or pulls the traffic that buys everything else — atta, milk, eggs and tea earn their shelf through volume. Judge the monthly rupee contribution, not the percentage.
How often should I review product profitability?
Monthly for the margin ranking, quarterly for keep-or-drop decisions, and weekly for anything with an expiry date. Dead stock found at day 60 can still be recovered; at day 200 it is a write-off.