How to Calculate Selling Price for Online Products: COGS, Platform Fees, and Margin
Most small sellers price by feel. Buy for Rp 40,000, sell for Rp 60,000, pocket the difference, sounds right, right? Then the marketplace takes its cut, shipping eats a few thousand, and that comfortable-looking margin quietly shrinks to almost nothing. I’ve watched sellers work for a year before realizing they were basically donating their time.
Pricing isn’t guesswork. It’s three numbers and one formula, and this guide walks through all of it with real math.
The costs you’re probably forgetting
Your actual cost per unit is more than what the supplier charges:
- Product cost: what you pay the supplier, or materials if you make it yourself.
- Packaging: box, bubble wrap, tape, the little thank-you card. Usually Rp 2,000 to 5,000 an order and people forget it constantly.
- Platform fees: marketplace admin cuts run roughly 5 to 12 percent depending on platform and category.
- Payment fees: per-transaction charges on some channels.
- Shipping subsidy: offering “free shipping” means you pay what the buyer doesn’t.
- Ad cost per sale: running ads? Divide spend by orders produced. That number is part of your cost whether you like it or not.
The first two added together give you COGS (HPP). Everything else stacks on top.
The two formulas
COGS: product cost + packaging + direct production cost.
Selling price with platform fee and target margin:
Price = COGS / (1 – platform fee% – margin%)
Quick note on margin: it’s margin on the selling price, the way platforms and accountants measure it. A 30 percent margin means you keep Rp 30,000 of every Rp 100,000 the buyer pays.
Worked example: a stainless tumbler
Real numbers:
- Supplier price: Rp 45,000
- Packaging: Rp 3,000
- COGS: Rp 48,000
- Platform fee: 10 percent
- Target margin: 30 percent
Price = 48,000 / (1 – 0.10 – 0.30) = 48,000 / 0.60 = Rp 80,000
Check it: buyer pays 80,000. Platform takes 8,000. COGS takes 48,000. You keep 24,000, exactly 30 percent. Clean.
Now watch what “pricing by feel” at Rp 65,000 does instead: platform takes 6,500, COGS takes 48,000, you’re left with Rp 10,500, a 16 percent margin before any shipping subsidy or ad costs. That gap between 16% and 30% is the difference between a business and an expensive hobby.
Shipping and ads don’t disappear
Free shipping on that tumbler? If shipping averages Rp 12,000 to your typical customer, the honest price keeping your 30 percent is closer to Rp 90,000.
Running ads? If Rp 200,000 in ads produced 20 orders, add Rp 10,000 per order to your cost before calculating. Skip this and your “profit” is fiction.
Copy this template into a spreadsheet
| Line item | Amount (Rp) |
|---|---|
| Product cost | 45,000 |
| Packaging | 3,000 |
| COGS | 48,000 |
| Platform fee (%) | 10% |
| Shipping subsidy | 0 |
| Ad cost per sale | 0 |
| Target margin (%) | 30% |
| Selling price | 80,000 |
When a marketplace raises fees, you’ll see in ten seconds whether your margin survives or your price needs to move.
Bundles and discounts change the math
Bundles: calculate COGS on the whole bundle, price slightly below the sum of individual prices. Margin stays healthy, buyers feel the deal.
Discounts: calculate margin at the discounted price, not the full one. A 20 percent promo on an 80,000 item leaves Rp 8,000 profit, not Rp 24,000. Run the formula on the promo price before announcing the sale. Learned that one the expensive way.
When your price is above the market
Sometimes the formula gives a number buyers won’t pay. Don’t absorb the loss and hope volume saves you, work backwards instead. Take the market price, subtract the platform fee, subtract your margin, and what’s left is your maximum COGS.
Market pays Rp 60,000, fee is 10 percent, you want 30 percent: cost ceiling is 60,000 x 0.60 = Rp 36,000. Can’t source at that? The market is telling you this product doesn’t work, not that your math is wrong.
Mistakes that quietly lose money
- Margin on cost instead of price. Adding 30 percent to COGS isn’t a 30 percent margin. 48,000 + 30% = 62,400, which is only a 23 percent margin.
- Ignoring your actual fee tier. Fees vary by category and seller level. Check yours on the platform’s official page before calculating.
- Free shipping without repricing. It’s a cost. Full stop.
- No buffer for returns. Even 2 to 3 percent for broken or lost orders saves surprises.
- Set-and-forget pricing. Supplier costs and platform fees change. Recheck every few months.
- Copying competitor prices blindly. You don’t know their supplier deal or ad spend. Use their prices as a sanity check, not a formula.
Run the numbers
One small trick once the formula gives you a price: check it reads cleanly to buyers. Rp 79,000 often outsells Rp 80,000 at nearly the same margin, psychology is weird but free.
Then take your three best-sellers. Real COGS, actual platform fee, the margin you want. Two minutes per product. The sellers who actually run this math are the ones still in business next year.
