The question that comes up most in 3D printing groups is always the same: how much do I charge? Short answer: a five-part formula plus a margin. Long answer: how to apply it with real numbers in Mexican, Argentine, and Colombian pesos, so you stop guessing and start charging what your time and machine are actually worth.
The 2026 formula
The formula explained, part by part
Material, with waste
It's not the spool price divided by grams. It's that plus 8-15% extra, because prints fail, nozzles get recalibrated, and filament is lost in purges.
Power (electricity)
An FDM printer draws 80-150 W while printing. Multiply watts by printing hours and by your electricity rate per kWh.
Machine wear
Nozzles, belts, bearings, the printer itself. Divide what you paid for the printer by its estimated lifetime hours (around 3,000 h) and charge that fraction for every hour of use.
Labor
Designing, prepping the file, watching the print, sanding, removing supports, packing. That time has an hourly rate, whether it's you or an employee doing it.
Add those four costs and you have the real cost of producing the piece. Margin isn't a luxury: it's what lets you reinvest in filament, fix the printer when a belt snaps, and leave something for the business after expenses. Quick rule: multiply total cost by 1.4 (low margin, high volume) up to 2 (custom pieces, little competition).
How to find your real electricity cost
You don't need an engineer for this. Check your electricity bill for the price per kWh — the same number your utility uses to bill you, whether you print or not. Multiply it by your printer's consumption, usually listed on the power supply label or in the spec sheet (look for 'W' or 'power draw'). If you can't find it, 120 W is a reasonable average for a desktop FDM printer running. It's never the biggest cost in the formula, but adding it keeps you from giving away electricity every day without noticing.
How long a printer actually lasts
3,000 hours is a conservative, easy-to-use number, not a fixed rule. A well-maintained printer — nozzle changed on time, belts tensioned, rails clean — can pass 5,000 hours without major issues. One run without maintenance starts failing much sooner. If you don't know your printer's hours, count recent prints and multiply by average time: that gives you a baseline. The point isn't to nail the exact number, it's to not leave wear at zero, because that cost exists even if you don't see it until the printer breaks.
What to say when a customer says 'that's expensive'
It always happens. The answer isn't to blindly drop the price — it's to show what it's made of. If you know your real cost, you can explain in seconds why that piece can't cost the same as an injection-molded keychain from a chain store: there's design, a machine running for hours, and someone watching the process. When you don't know your cost, every objection makes you doubt yourself and you end up pricing below what it costs to produce. Having the formula ready, even in a simple spreadsheet, gives you the argument and keeps fear of losing the sale from making you work for free.
Example in Mexico (Mexican pesos)
Assumptions: PLA at $450 MXN/kg ($0.45/g), electricity at $2.5 MXN/kWh, an $8,000 MXN printer with 3,000 h lifetime ($2.67/h wear), labor at $80 MXN/hour. Adjust these to your real costs — they vary by city and supplier.
Custom keychain — 15 g, 1.5 h print (MXN)
| Item | Calculation | Cost |
|---|---|---|
| Material + waste | 15 g × $0.495/g | $7.43 |
| Power | 0.12 kW × 1.5 h × $2.5 | $0.45 |
| Machine wear | 1.5 h × $2.67/h | $4.00 |
| Labor | 20 min × $80/h | $26.67 |
| Total cost | $38.55 | |
| Suggested price (×2.2) | $85.00 |
Functional bracket — 120 g, 6 h print (MXN)
| Item | Calculation | Cost |
|---|---|---|
| Material + waste | 120 g × $0.495/g | $59.40 |
| Power | 0.12 kW × 6 h × $2.5 | $1.80 |
| Machine wear | 6 h × $2.67/h | $16.00 |
| Labor | 30 min × $80/h | $40.00 |
| Total cost | $117.20 | |
| Suggested price (×1.8) | $211.00 |
Example in Argentina (Argentine pesos)
Assumptions: PLA at $7,000 ARS/kg ($7/g), electricity at $150 ARS/kWh, a $1,200,000 ARS printer with 3,000 h lifetime ($400/h wear), labor at $3,000 ARS/hour. With high inflation, review these prices monthly — the formula doesn't change, the numbers do.
Custom keychain — 15 g, 1.5 h print (ARS)
| Item | Calculation | Cost |
|---|---|---|
| Material + waste | 15 g × $7.7/g | $115.50 |
| Power | 0.12 kW × 1.5 h × $150 | $27.00 |
| Machine wear | 1.5 h × $400/h | $600.00 |
| Labor | 20 min × $3,000/h | $990.00 |
| Total cost | $1,732.50 | |
| Suggested price (×2) | $3,500.00 |
Functional bracket — 120 g, 6 h print (ARS)
| Item | Calculation | Cost |
|---|---|---|
| Material + waste | 120 g × $7.7/g | $924.00 |
| Power | 0.12 kW × 6 h × $150 | $108.00 |
| Machine wear | 6 h × $400/h | $2,400.00 |
| Labor | 30 min × $3,000/h | $1,500.00 |
| Total cost | $4,932.00 | |
| Suggested price (×1.8) | $8,900.00 |
Example in Colombia (Colombian pesos)
Assumptions: PLA at $35,000 COP/kg ($35/g), electricity at $800 COP/kWh, a $3,000,000 COP printer with 3,000 h lifetime ($1,000/h wear), labor at $15,000 COP/hour.
Custom keychain — 15 g, 1.5 h print (COP)
| Item | Calculation | Cost |
|---|---|---|
| Material + waste | 15 g × $38.5/g | $577.50 |
| Power | 0.12 kW × 1.5 h × $800 | $144.00 |
| Machine wear | 1.5 h × $1,000/h | $1,500.00 |
| Labor | 20 min × $15,000/h | $4,950.00 |
| Total cost | $7,171.50 | |
| Suggested price (×2) | $14,300.00 |
Functional bracket — 120 g, 6 h print (COP)
| Item | Calculation | Cost |
|---|---|---|
| Material + waste | 120 g × $38.5/g | $4,620.00 |
| Power | 0.12 kW × 6 h × $800 | $576.00 |
| Machine wear | 6 h × $1,000/h | $6,000.00 |
| Labor | 30 min × $15,000/h | $7,500.00 |
| Total cost | $18,696.00 | |
| Suggested price (×1.8) | $33,700.00 |
The pattern repeats across all three countries
Labor and machine wear usually outweigh material. That's why charging 'just for the filament' always ends in a loss. The formula is the same in any currency: only your local rates change.
How often to recalculate your prices
In high-inflation countries, review filament price and electricity rate monthly — an 80% margin today can drop to 40% in eight weeks if you don't adjust. In more stable countries, a quarterly review is enough, unless your filament supplier's price changes or your electricity rate jumps suddenly. The signal to recalculate now, without waiting for the schedule, is simple: if you notice you're buying material more often than usual for the same sales volume, your margin has already been eaten by inflation without you noticing.
Mistakes that cost you money
What changes between Mexico, Argentina, and Colombia
The cost structure is the same in all three countries: material and labor outweigh power and wear. What changes is the proportion. In Argentina, with electricity rates low relative to labor, power barely shows up in the total — labor hours weigh much more. In Mexico and Colombia, material carries more relative weight because imported filament tends to cost more in dollars per kilo than local labor hours. The practical lesson: don't copy another country's margin as-is. Run your own numbers with your own rates and adjust the multiplier based on how much each item weighs in your structure.
Packaging, shipping, and other costs that slip through
The five-part formula covers what happens at the printer, but a real business has more costs around it. Bag or box, tape, label, the time to assemble the package: add it as part of labor or as a separate small line per order. Shipping is almost never absorbed — charge it separately and tell the customer up front in the quote, so it's not a surprise at checkout. And if you sell through a platform that charges a commission (marketplace, payment gateway), that commission also comes out of the final price, not the margin you already calculated. Ignoring these extras is one of the most common ways to see 'good sales' that still leave no profit at month's end.
What margin to apply by piece type
Suggested margin by product type
| Piece type | Suggested margin | Why |
|---|---|---|
| Volume pieces (keychains, souvenirs) | 40-60% | Competitive price, high turnover |
| Functional pieces (brackets, spare parts) | 60-90% | Solve a problem, little local competition |
| Custom / made-to-order pieces | 100% or more | Design time and exclusivity |
Don't calculate this by hand every time
MiNegocio3D's calculator applies this exact formula automatically: enter material, printing time, and your local rates, and it gives you the price with margin included. Try it free at minegocio3d.com/calculadora.