About Filacoste
Who is behind it, where every number comes from and why this site asks nothing of you in return.
Who writes this
My name is Álvaro Melgar Merenciano and Filacoste is mine.
I had two 3D printers and I sold printed parts — specifically, parts with an NFC chip inside. That is not a decorative detail: putting an NFC chip inside a part means pausing the print halfway up, placing the chip in its recess and resuming. That is minutes of your own time on every single unit, and if the pause goes wrong the whole part is scrap.
That is where I realised that the sum everybody does — me first of all — did not add up. You divide the price of the spool by the grams, you get that the part costs a euro and a bit, and you carry on happily. But the time spent watching that pause is not in there. Nor the part that came unstuck at four hours. Nor the chip. Nor the envelope. Nor the machine hours that part took away from another one.
Filacoste came out of that sum that did not add up. First it was a spreadsheet to work out whether I was making money or paying for the privilege of working; then it became this.
What Filacoste is
Filacoste (from filament + coste, Spanish for cost) is a site with four calculators and twelve guides about the cost of 3D printing. The calculators do the arithmetic; the guides explain where each field comes from.
The calculators that existed belonged to particular manufacturers, or lived buried in somebody's blog. I wanted one that worked the same with a Bambu Lab, a Creality, an Elegoo or a Prusa, and that was built for quoting a customer, not just for satisfying curiosity.
How the cost is worked out
The formulas are in plain sight and they are the same across the whole site: material, electricity, machine depreciation, a percentage of failed prints and your labour. Your markup is applied on top of that cost. You can see the full breakdown in the cost calculator.
The tables in the guides are worked out with those same formulas, so the site never contradicts itself.
Why the figures in the articles always add up
This is the part I am happiest with, and it is an odd one to explain because you cannot see it.
Every time a number appears in a guide — that a part costs 5.11 €, that a failure halfway through is 2.96 €, that a job of twelve parts comes to 105.42 € — that number is also written into an automatic checker that recalculates it with the site's real formulas and compares it with what the text says.
If one day I change an assumption — the price of a kWh, the working life of the machine — and forget to update a paragraph, the checker does not let me publish. Right now there are nearly four hundred checks of that kind.
I mention it because it is the difference between quoting a figure from another blog and calculating it. Every figure here is calculated.
What I do not do
I do not ask you to sign up, or for an email, or for an account.
I do not upload anything. If you drop a G-code file in, it is read inside your browser and never leaves your computer.
I do not convert currencies. The currency selector only changes how the amounts are formatted, and I say so where it matters.
I do not invent official data. Printer wattages are estimated averages and filament prices are ranges, not price lists. When I cannot calculate something, I either cite the source or say I do not know.
How it is kept going
The site is free and it is supported by advertising: that is what pays for it to exist and to stay free. The ads are placed automatically by Google, so exactly where they land is not my decision. If one of them covers the tool or gets in the way of calculating, write to me and I will adjust it.
What it is built with
HTML, CSS and JavaScript, with no framework at all. The calculators run entirely in your browser: the weights, times and prices you type are not sent to any server. What the site does load is the Google AdSense script, which is what pays for this to exist and the only external service involved; I set it out in the privacy policy.
The typefaces are Inter and Space Grotesk, both under the SIL Open Font License 1.1 and hosted here, with the full text of the licence next to the files.
The header photos on the guides are public domain (CC0) and I found them on Openverse. I keep a record of where each one came from in case anybody needs it.
Mistakes and suggestions
If a number does not add up for you, if your printer is missing from the list or if you find yourself wanting a tool that is not here, write to me from the contact page. Corrections to the arithmetic take priority over everything else: if you find one, tell me the figures you used and I will reply with the sum worked out.
More tools and guides
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.
How much does 3D printing cost: 20 parts with real numbersThe real cost of 20 typical 3D printed parts: keyring, planter, phone stand, gear and more, with their grams, their hours and a link to recalculate.
Why 3D prints fail and what it really costs youA failure halfway through costs 2.96 €, and only 32% of that is material. The four causes in order, with the real annual cost of each failure rate.
How long does a 1 kg filament spool lastHow many metres and how many parts you get from a 1 kg spool, by material and diameter. Tables for PLA, PETG and ABS, and how to gauge what is left.