How much to charge per gram for 3D printing is one of the most repeated questions, and the honest answer is: it depends on the part. A price per gram is convenient because customers understand it and you can calculate it fast, but it hides a problem: two parts that weigh the same can tie up your machine for 3 hours or 8. Here you'll see when to charge per gram, per minute, or per part, how to convert your hourly cost into each unit, and which traps to avoid. The numbers are example assumptions, not market rates.
How much to charge per gram for 3D printing: where that number comes from
A price per gram isn't a fact of the universe, it's an average of your own costs. It blends material (filament or resin), machine time, wear, electricity, and your work, and spreads it across the grams your production usually weighs. If your mix of parts changes, that average stops being true. That's why copying another shop's price per gram is risky: you don't know which costs or what kind of parts are behind it.
The material cost per gram is easy to get; if you print in PLA, the method is in [what a gram of PLA costs](/en/blog/costo-por-gramo-pla). The hard part is converting the rest of your costs, which are measured in hours, into a unit of weight. That's what we solve next.
How to convert your hourly cost to grams and minutes
Start with your machine cost per hour: electricity, wear, and the share of fixed expenses you want to spread over each printing hour. If you don't have it yet, see [how to calculate a printer's cost per hour](/en/blog/amortizacion-impresora-3d-costo-por-hora) and [how much to charge per hour](/en/blog/cuanto-cobrar-por-hora-impresion-3d). From there, the conversions are two divisions.
From cost per hour to cost per gram
For the minute it's even simpler: divide the hourly cost by 60. And to find your grams per hour, take parts you've already printed: weight in grams divided by print hours. Notice how much the result changes with the type of part.
Converting an hourly cost of 1.00 USD (assumption) to minutes and grams
| Part type (example) | Grams per hour | Cost per minute | Machine cost per gram |
|---|---|---|---|
| Hollow or thin part, fine layers | 10 g/h | 0.017 USD | 0.10 USD |
| Medium-sized part | 20 g/h | 0.017 USD | 0.05 USD |
| Solid part, thick layers | 40 g/h | 0.017 USD | 0.025 USD |
The cost per minute is always the same (1.00 ÷ 60 ≈ 0.017 USD), but the cost per gram is multiplied by four depending on how fast your part piles up weight. That's the key: the minute measures what it costs to occupy the machine; the gram is only a good approximation if your parts tend to be similar.
Per minute or hour
It measures exactly what the machine consumes. It's the most faithful method for long, delicate, or fine-layer parts, where weight is misleading.
Per gram
It's simple and easy to explain. It works when you sell many similar parts or when material is most of the cost.
Per part
It's what the customer wants to see. But that fixed price should come from a real-cost calculation, not a number pulled from thin air.
The trap of charging by gram alone
Here's the example with assumptions. Two parts weigh 60 g each. The first prints in 3 hours with thick layers; the second takes 8 hours because it has fine layers and detail. Assumptions: filament at 0.02 USD per gram with 5% waste, machine cost of 1.00 USD per hour, and 10 minutes of hands-on work at 6 USD an hour (1.00 USD).
Same weight, different cost (USD, assumptions)
| Item | Part A (3 h) | Part B (8 h) |
|---|---|---|
| Material: 60 g × 0.02 × 1.05 | 1.26 | 1.26 |
| Machine: hours × 1.00 | 3.00 | 8.00 |
| Hands-on work: 10 min | 1.00 | 1.00 |
| Total cost | 5.26 | 10.26 |
| Charging 0.12 USD per gram (7.20) | You earn 1.94 | You lose 3.06 |
| Price with a 40% margin on cost | ≈ 7.36 | ≈ 14.36 |
With the same rate per gram, part A makes you money and part B loses money, even though both weigh the same. If your customers order a lot of the second kind, your average price per gram falls short without you noticing. The reverse happens too: a solid, fast part leaves you a huge margin that may make you look expensive next to other shops.
A price per gram needs review too
If you use a price per gram, recalculate it from time to time with your real parts: add up your monthly costs, divide by the grams you printed, and compare with what you charge. And set a minimum price per order, because a part of just a few grams doesn't even cover the time to prepare the file.
When to charge per gram, per minute, or per part
Which method to use depending on your situation
| Situation | Recommended method | Why |
|---|---|---|
| Many parts similar in weight and time | Per gram | The average works and quoting is fast |
| Long, large, or fine-layer parts | Per minute or hour | Machine time is the biggest cost |
| Products you always sell the same (catalog) | Per part | You calculate the real cost once and fix the price |
| Custom jobs with design or post-processing | Per part, with a full calculation | Hands-on work outweighs material |
| Orders with several different parts | Quote per part and total | Each part has its own cost |
In practice, many shops calculate the real cost per part and then show the customer a final price per part. The gram and the minute stay as internal tools to check that the price makes sense. And to run these numbers with your own data, there is the [free calculator](/en/calculator).
Frequently asked questions
What is a good price per gram in 3D printing?+
Is it better to charge per gram or per hour?+
How do I turn my hourly cost into a cost per minute?+
Should I charge hands-on work separately from the gram and the minute?+
Let the system do the conversion
In MiNegocio3D the real cost of each part already includes material with waste, electricity, wear, and time, so you don't depend on an average price per gram. From 17 USD a month, with a 7-day free trial, no card required, and a 30-day guarantee.