Break-even point: how many parts you have to sell

“It costs me 1.20 € of plastic and I sell it for 20.00 €.” That is the sentence almost everybody starts with, and the reason most people do not know whether they are making money.

The plastic is less than a quarter of what that part costs. And what is left after paying for everything is not your wage: your wage was already inside. This article is the sum of how many parts a month you need for the business to stop costing you money, which is a different and more useful question.

Your time is 59% of the cost

This site's reference part — 60 grams of PLA, 5 h 30 of printing, a quarter of an hour of your own between removing it, cleaning and packing — costs 5.11 €. This is how it breaks down:

The plastic, which is the only thing almost everybody counts, is 23%. The electricity, which is what worries people most, is 2%. And your time, which is what almost nobody counts, is more than half.

That has a direct consequence for the price. If you do not pay yourself those fifteen minutes, the cost comes to 2.11 € and at the default markup you would put the part at 3.16 € instead of 7.66 €. Four and a half euros of difference on a small part, and on top of that you think you are making 1.05 €. You can see it yourself: the calculator with working minutes set to zero.

What each part actually leaves you

At the catalogue price of 7.66 €, every part sold leaves 2.55 € above what it costs to produce. That number governs everything else, because it is the only thing available to pay for any expense that does not depend on the parts.

It goes up or down with the markup you set:

The last column is the usual one: a 50% markup is not a 50% margin, it is 33%. To have a margin of half the price you have to mark up double.

The break-even point, in parts per month

Now the real question. There are expenses that do not depend on how much you print: a marketplace subscription, a domain, a stall at a fair, software, the design hours. Those have to be paid whether you sell two parts or two hundred.

The break-even point is a division: that fixed expense divided by the 2.55 € each part leaves.

Read the last column, because that is the one that surprises. Covering 100.00 € a month of fixed costs is forty parts and 220 hours of printer time: seven hours and change every single day of the month. And that is just to reach zero.

Below that number you are not earning little: you are losing. Selling nineteen parts with 50.00 € of fixed costs means putting money in.

The markup moves the point more than anything else

With the same 50.00 € of fixed costs, what changes the number of parts is not what you spend on filament: it is what you charge.

From 49 parts down to 10. It is the same part, the same filament and the same printer: the only thing that changes is the price on the label.

This is worth being clear about because instinct pulls the other way. When the sums do not work, the first thing people try is cheaper filament. Dropping the spool from 20.00 € to 16.00 € saves 26 cents per part. Raising the markup from 50% to 80% adds 1.53 € per part: nearly six times as much, without changing anything you do.

The printer has its own break-even point

There is one expense the calculator already spreads for you, and it is worth a close look because it hides a trap. The 400.00 € machine with 50.00 € of maintenance is spread over 4,000 hours of working life, which comes to 68 cents per part.

To recover those 450.00 € you need 662 parts. The rate you sell them at decides whether the printer pays for itself or not:

And here is the trap: spreading the machine over 4,000 hours assumes you are going to reach 4,000 hours. If you print twenty parts a year that is 110 hours a year, and at that rate you would take thirty-six years to use up its working life. No printer survives that: it goes obsolete, it breaks with no spares left, or you simply stop wanting to use it.

Put another way: depreciation per hour is only honest if you really are going to use the machine. If you print little, the sensible thing is to count the printer for what it is — a fixed cost you have already paid — and put it into the division above with the rest.

When one printer stops keeping up

The other limit is not about money, it is about hours. Each part occupies the machine for 5 h 30, and the month has the hours it has.

With the printer running twelve hours a day, which already means having it work half a full day every day, the ceiling is 65 parts a month. At twenty-four hours a day, without sleeping and without a single failure, 131.

That makes the ceiling fairly clear. If your numbers need more than sixty-five parts a month, the problem is no longer solved by selling more: you need another machine, and another machine is another fixed cost that moves the break-even point again.

Selling on a marketplace doubles the point

Everything above assumes you collect the full 7.66 €. If you sell on a platform, you do not.

With Etsy's fees — 6.5% transaction, $0.20 listing and 4% plus 0.30 € for payment processing — a sale of 7.66 € leaves 1.28 € in fees. That is exactly half of what the part was leaving you: half your contribution goes before you can use it for anything.

At the default markup, the break-even point goes from 20 parts to 40. Exactly double, for selling in the same place where the buyers are.

That is not an argument against selling there: it is an argument against using the same price inside and outside. The full breakdown of what each item takes is in the Etsy fees guide, and if you also invoice with VAT, in the VAT guide.

Design time is a fixed cost too

The hours you spend modelling are the easiest fixed cost to forget, because they do not come out of your pocket: they come out of your afternoon. But they behave just like a subscription, and so they have their own break-even point.

If on top of that you have 50.00 € of fixed costs a month, the fifteen parts of the design add to the twenty of the subscription. Thirty-five parts before the first euro. How to charge for design time has the way to put it into the price instead of swallowing it.

A whole month, line by line

Forty parts sold in a month, at the default 50% markup, with 50.00 € of fixed costs:

Fifty-two euros of profit may look like little for a month of work. But inside those 204.38 € of cost there are 120.00 € that are yours: the ten hours you put into the forty parts, already paid at 12.00 € an hour.

What goes into your pocket is 172.19 €, which across those ten hours comes to 17.22 € an hour. That is the honest figure, and it is rather better than it looked from the profit line alone.

What the table does not show is the 220 hours of printer time, more than seven a day. A month of forty parts fits easily in one machine; a month of a hundred does not.

The mistakes that move the point without you noticing

Not paying yourself for your time. This is the big one. Your time is 59% of the cost, so leaving it out is not a tweak: it is deleting more than half the sum and believing that the 3.16 € price is real.

Counting the printer twice. If you put it in the fixed costs and leave the depreciation in the calculator, you are paying for it twice. One of the two, not both.

Using the catalogue price to work out break-even on a sale with fees. They are two different numbers: 20 parts outside, 40 inside Etsy.

Forgetting that break-even is monthly. A 50.00 € subscription is 20 parts every month. If one month you sell 35 and the next you sell 5, you have not covered two months: you have covered one and a half.

Chasing cheap filament. Four euros off the spool is 26 cents per part. Thirty more points of markup is 1.53 €. The money is not in the purchase, it is on the label.

Do it with your own figures

It is three steps and none takes more than a minute.

One. Get your part's real cost in the cost calculator, with your grams, your hours and — above all — your working minutes actually filled in.

Two. Put your price into the pricing calculator and note the difference between price and cost. That is what each part leaves. Try it with the markup at 100% too, to see how much it moves.

Three. Add up everything you pay monthly regardless of how much you print — subscriptions, domain, software, fairs, the spread design hours — and divide by what each part leaves. That is your number.

Then do the check nobody does: multiply that number by the hours each part takes. If the result does not fit in the month, the plan is not failing on price, it is failing on the machine.

More tools and guides

• What you actually keep when you sell 3D prints on EtsyWhat Etsy really takes from each sale in the eurozone: 12.5% normally, 27.5% with Offsite Ads. With the table of what is left at every price.
• VAT on selling 3D printed parts: what you actually take homeOf 20 € listed you keep 8.95 €. How VAT works on printed parts, the 10,000 € threshold and the One Stop Shop if you sell to other EU countries.
• How to charge for design time in 3D printingDesign is not charged per part: it is spread. Three hours are 36.00 € that come to 1.80 € each across 20 units, and to 36.00 € on a single one.
• 3D printing cost calculatorWork out the real cost and selling price of a 3D printed part: material, power, machine wear, failures and markup. Free, no sign-up, nothing uploaded.
• How much to charge for a 3D printed partPrice your prints properly: real cost, your labour and your markup. Generates a quote you can copy and send straight to the customer.
• How much electricity does a 3D printer useWork out your 3D printer's power use and what it costs per month on your own tariff. With the average wattage of the most common models.

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