3D Print Pricing Calculator

How selling fees stack

Two fees usually apply to the same sale, and they are charged on the sale price rather than on your cost:

• A marketplace commission. A percentage of the item price, sometimes with a small fixed component per order. It is charged whether or not you made a profit.
• A payment processing fee. A percentage plus, often, a small fixed amount. It sits on top of the marketplace fee rather than replacing it.

Together they take a bite out of the top line, not the bottom. That single fact is what makes the arithmetic on this page a division rather than an addition.

Why you cannot just add a percentage to your cost

Suppose a part costs $3.84 to produce and you want to keep 30% on top. Multiplying by 1.30 gives $4.99. Charge $4.99 on a platform taking 10% and you receive $4.49 — which leaves $0.65, or about 17%, not 30%.

The fee is a share of the price, so the price has to be grossed up:

With the numbers above that gives $3.84 × 1.30 ÷ 0.90 = $5.55. The 30% margin then survives the fees instead of being eaten by them. On a $3.84 part, getting this wrong costs you about 50 cents a unit — which across a batch of fifty is a fortnight's filament.

Worked example: a $3.84 part with postage

A part that costs $3.84 to produce, $2.50 of postage paid and $2.50 charged to the buyer, a 30% target margin, and a 6.5% platform fee plus a 3.5% payment fee:

The break-even row is the one to keep in your head. It is what you would have to charge to make exactly nothing. Anything above it is a business; anything below it is a hobby with an invoice.

What to do about postage

Postage is where most small sellers quietly lose money, because it is charged as a guess and paid as a fact. Three ways to handle it, in ascending order of safety:

1. Charge the full amount. The buyer covers postage exactly and it disappears from your costing. Simplest, and it makes your item price honest.
2. Charge a flat amount and absorb the rest. Common, and fine as long as the absorbed amount is inside your margin. Enter the difference in the fields above and the calculator will price around it.
3. Build postage into the item price. Offer free shipping and raise the price to cover it. Workable, but remember the platform fee is then charged on the postage you just folded in.

What does not work is charging a flat $2.50 everywhere while some orders cost $6.00 to send. That is a subsidy you are funding out of the margin, and it tends to show up all at once in a bad month.

When to price at break-even on purpose

There are two good reasons to sell at or near break-even, and both are temporary. First, clearing stock of an item that is not moving: recovering the material is better than storing it. Second, buying a first review on a new listing, where the review itself has a value that shows up later.

Both cases require you to know the break-even figure, which is exactly what this calculator returns. Pricing near break-even by accident is a different thing entirely, and it is what happens when fees are left out of the arithmetic.

Important assumptions

Fees are treated as a single combined percentage on the item price, and postage is treated as excluded from commission. Both are simplifications. Real marketplace schedules often add a small fixed fee per order, charge a different rate by category, or include shipping in the commission base. Read your own platform's fee page and adjust the two percentage fields to match — the whole point of the fields is that the schedule is yours, not ours.

The margin field is what you want to keep, not a recommended rate. This page does not know your market, your competition or what your time is worth.