Calculate filament cost, total print cost, and remaining filament on any spool
3D printing has transformed prototyping, manufacturing, and creative making—but understanding what each print actually costs is surprisingly tricky. The price of a spool is only the beginning. You also need to account for electricity consumed during a multi-hour print, the labor time for setup and post-processing, machine depreciation that slowly chips away at your printer investment, and the material waste that inevitably occurs with supports, failed tests, and purge lines. Our 3D Printing Filament Calculator brings all of these factors together in one place so you can quote jobs accurately, price products for sale, or simply understand what your hobby is really costing you. At the core of the tool is the material cost calculation: how much of the spool did you actually use, and what does that portion of the spool cost? This is straightforward arithmetic—grams used divided by total spool grams, multiplied by spool price—but many makers overlook the waste factor. Real-world printing typically wastes 5–10% of consumed filament on skirts, brims, rafts, ooze, and purge. The default 8% waste buffer ensures your estimate stays realistic rather than optimistic. The electricity cost section is indispensable for print farms and anyone selling prints. A printer running at 200 watts for 8 hours consumes 1.6 kWh. At $0.12/kWh that is only $0.19—seemingly negligible—but at the scale of hundreds of prints per month, or with an industrial printer pulling 400+ watts, electricity becomes a significant line item. The calculator uses your actual printer wattage and local electricity rate to compute the exact energy cost for each job. Labor cost is perhaps the most underestimated expense in home and small-scale 3D printing businesses. Every print requires prep time—slicing, loading filament, leveling the bed, starting the job—and post-processing time for removing supports, sanding, painting, and packaging. The labor section lets you specify prep minutes, post-processing minutes, and an hourly rate, computing the true human cost behind each part. Machine depreciation converts your printer purchase price into a per-print cost. A $300 printer used for 3 years at 6 hours per day provides roughly 6,570 hours of printing. That is about $0.046 per hour. On a 10-hour print that adds $0.46 to your cost—important for accurate long-run accounting, especially if you are selling prints or running a print-on-demand service. Add a repair/maintenance percentage (typically 5% of printer value annually) and you have a complete overhead picture. The markup and VAT fields allow you to convert your raw cost into a suggested selling price. Enter your target profit margin as a percentage and the calculator shows you the minimum price you should charge. The per-item calculation is especially useful when printing multiple copies on one plate, as you divide the total plate cost among all items. The Remaining Filament mode answers the maker's most common question: how much is left on this partial spool? By weighing the spool and entering both the current weight and the empty spool weight, the calculator derives the remaining grams of filament, then converts that weight into meters using the material density and filament diameter formula. Knowing you have 85 meters left versus 15 meters can determine whether you start a long print tonight or order a new spool first. Supported materials include PLA (1.24 g/cm³), PETG (1.27 g/cm³), ABS (1.05 g/cm³), ASA (1.07 g/cm³), TPU (1.21 g/cm³), Nylon/PA6 (1.14 g/cm³), PC (1.20 g/cm³), PETT (1.27 g/cm³), PPS (1.34 g/cm³), PEEK (1.30 g/cm³), and Carbon Fiber Nylon (1.09 g/cm³). Each material auto-populates its standard density, which you can override for specialty blends or proprietary filaments. The tool supports both 1.75mm and 2.85mm diameter filament, covering the vast majority of consumer and prosumer printers on the market.
Understanding 3D Printing Costs
What Goes Into 3D Printing Cost?
A complete 3D printing cost includes five major components: material cost (the filament itself, plus a waste factor for supports and purge), electricity cost (printer wattage times print duration times your utility rate), labor cost (setup, monitoring, and post-processing time multiplied by an hourly rate), machine depreciation (amortizing the printer purchase price over its expected lifespan and usage hours), and maintenance cost (annual repair and upkeep estimated as a percentage of printer value). For hobbyist use, material cost dominates—typically 70–90% of total cost on a home printer. For professional print services and print farms, electricity and labor become significant, sometimes comprising 30–50% of total cost at scale.
How Are Filament Costs Calculated?
Material cost uses the formula: (grams used ÷ spool total grams) × spool price × (1 + waste%). This pro-rates the spool cost by the fraction consumed. Filament length is derived from weight using: Length (m) = (mass_g × 4) ÷ (density_g/cm³ × π × diameter_mm²). This formula comes from the physical geometry of a cylinder—the filament cross-section is π×(d/2)², and dividing the mass by volume per unit length gives total length. Electricity: (watts ÷ 1000) × print_hours × $/kWh. Labor: ((prep_min + post_min) ÷ 60) × hourly_rate. Depreciation: printer_cost ÷ (daily_hours × 365 × years) × print_hours. Maintenance: (printer_cost × repair%) ÷ (daily_hours × 365) × print_hours.
Why Accurate Cost Tracking Matters
Accurate cost tracking prevents two common mistakes: underpricing when selling prints, and being surprised by hobby expenses. Many makers set prices based on filament cost alone and forget that a 12-hour print at $0.25 in filament still consumed $0.30 in electricity and required 45 minutes of labor worth $15. The true cost might be $16.55, but the listed price is $3. For businesses, this leads to losses. For hobbyists, it distorts budget planning. Understanding your full cost also helps you optimize: switching to a faster but slightly more expensive material might lower total cost if it cuts 4 hours of electricity and machine time. Tracking per-gram and per-meter costs makes filament brand comparisons objective rather than guesswork.
Limitations and Assumptions
This calculator assumes constant printer power consumption throughout a print, which is not technically accurate—printers draw more power during heating phases and less during travels. The actual consumption is typically 60–80% of the rated maximum wattage averaged over a print. Entering 70% of your printer's max wattage gives a more realistic estimate. Material density values are standard averages; specialty filaments, composite blends, and low-quality filaments may differ significantly. The waste factor default of 8% is appropriate for typical FDM prints with supports; low-support or vase mode prints waste less. The depreciation model assumes uniform daily usage—burst usage or extended idle periods will skew per-print overhead. Labor rates are entirely subjective and should reflect your actual opportunity cost or local market rate for similar skilled work.
Formulas
Pro-rates the spool price by the fraction of filament consumed, with an added waste factor to account for supports, purge lines, skirts, and failed prints.
Converts filament weight to length using cylinder geometry. The cross-sectional area of the filament (π × r²) combined with density gives volume per unit length, which is inverted to get length per unit mass.
Converts printer wattage to kilowatts, multiplies by print duration in hours, then by your local electricity rate to get total energy cost for the print job.
Amortizes the printer purchase price over its expected total operating hours, then multiplies by the hours consumed by this specific print to get per-job overhead.
Reference Tables
Common Filament Material Densities
| Material | Density (g/cm³) | Typical Spool Price (1 kg) | Meters per kg (1.75 mm) |
|---|---|---|---|
| PLA | 1.24 | $18–25 | ~336 m |
| PETG | 1.27 | $20–28 | ~328 m |
| ABS | 1.05 | $18–24 | ~396 m |
| ASA | 1.07 | $25–35 | ~389 m |
| TPU (95A) | 1.21 | $25–40 | ~344 m |
| Nylon (PA6) | 1.14 | $30–50 | ~365 m |
| PC | 1.20 | $30–45 | ~347 m |
| PEEK | 1.30 | $300–500 | ~320 m |
| CF Nylon | 1.09 | $45–70 | ~382 m |
Typical Waste Factors by Print Type
| Print Type | Waste Factor | Notes |
|---|---|---|
| Vase mode / no supports | 2–3% | Minimal waste — only skirt and ooze |
| Standard print with skirt | 5–8% | Skirt, brim, minor stringing |
| Print with supports | 8–15% | Support material is discarded after removal |
| Multi-color (AMS/MMU) | 15–25% | Purge tower waste per color change |
| Prototype / test prints | 10–20% | Includes failed attempts and iterations |
Worked Examples
Basic Filament Cost for a PLA Print
Effective filament used = 45 g × (1 + 0.08) = 48.6 g
Fraction of spool = 48.6 ÷ 1000 = 0.0486
Material cost = 0.0486 × $22 = $1.07
Full Print Cost with Electricity and Labor
Material: (120 × 1.08 ÷ 1000) × $28 = 0.1296 × $28 = $3.63
Electricity: (200 ÷ 1000) × 8 × $0.12 = 0.2 × 8 × 0.12 = $0.19
Labor: ((15 + 30) ÷ 60) × $20 = 0.75 × $20 = $15.00
Total = $3.63 + $0.19 + $15.00 = $18.82
Remaining Filament on a Partial Spool
Net filament weight = 650 − 192 = 458 g
Length = (458 × 4) ÷ (1.24 × π × 1.75²) = 1832 ÷ (1.24 × 3.1416 × 3.0625)
Length = 1832 ÷ 11.926 = 153.6 m
How to Use the 3D Printing Filament Calculator
Select Material and Diameter
Choose your filament type from the material dropdown — PLA, PETG, ABS, ASA, TPU, Nylon, PC, or others. The material density auto-fills based on standard values but you can override it for specialty blends. Select your filament diameter (1.75mm or 2.85mm).
Enter Filament Usage and Spool Info
Enter the grams of filament used (found in your slicer software after slicing the model), your spool price, and the total spool weight in grams. For a standard 1 kg spool enter 1000g. The calculator uses these three values to determine the material cost fraction.
Add Optional Cost Sections
Expand the Electricity, Labor, and Depreciation sections to add more cost components. Enter your printer's wattage and electricity rate for energy cost. Add prep and post-processing minutes with an hourly rate for labor. Enter printer purchase price and usage hours for depreciation and maintenance.
Review Cost Breakdown and Export
The results show total cost, suggested selling price, cost per item (for batch prints), and a visual donut chart showing the proportion of each cost component. Use Export CSV to save the breakdown for records, or Print Results for a paper copy. Switch to Remaining Filament mode to check how many meters are left on a partial spool.
Frequently Asked Questions
How do I find out how many grams of filament a print uses?
Your slicer software calculates this automatically when you slice a model. In PrusaSlicer, look for the filament weight in the print statistics panel on the right side. In Cura, it appears at the bottom of the screen after slicing. In Bambu Studio, check the print preview panel. The grams value includes all material: walls, infill, supports, brim, and skirt. Enter this value directly into the 'Filament Used' field. If you are printing from a pre-sliced file without re-slicing, you can also weigh the printed part and any removed supports combined as an approximation.
What is the waste factor and what percentage should I use?
The waste factor accounts for filament that is consumed but does not end up in the final part. This includes the skirt lines printed before the actual part, purge blobs when switching colors, stringing and ooze, failed print attempts, and a small amount of filament remaining in the PTFE tube and hotend that cannot be used. For typical single-material prints with a skirt and minimal supports, 5–8% is appropriate. For multi-material prints with frequent purges on an AMS or similar system, 15–25% waste is realistic. For simple vase-mode prints with no supports or brim, 2–3% is sufficient. The default of 8% works well for most standard FDM prints.
How do I find the empty spool weight for remaining filament calculations?
The empty spool weight is printed on many spools, often as 'NW: 1000g' (net weight) and 'GW: 1210g' (gross weight), which implies an empty spool of 210g. If not labeled, common empty spool weights are: Prusament cardboard spool ~117g, Prusament plastic spool ~190g, eSun plastic ~200g, Bambu Lab ~165g, Hatchbox plastic ~220g, and generic Chinese spools ~190–250g. You can also weigh a completely empty spool if you have one of the same brand. If you are unsure, use 192g as a reasonable default for most consumer plastic spools — this is the weight used by several filament brands in their specifications.
Should I enter the printer's maximum rated wattage or average wattage for electricity calculations?
Enter the average wattage rather than the maximum. Most 3D printers list a maximum power draw on the label (e.g., '350W' on a Bambu X1 Carbon), but this is the peak during initial heating. During a steady-state print, average consumption is typically 50–70% of the rated maximum. For a Bambu X1 Carbon, actual average consumption during printing is around 200–250W, not 350W. For a standard Ender 3, the 200W rating is a reasonable average since it heats frequently throughout printing. Prusa MK4 typically averages 80–100W in practice. If you want the most accurate result, you can measure actual consumption with a smart plug or power meter and use that real-world figure.
How should I price prints when selling them?
Start with the fully-loaded cost from this calculator — including material with waste, electricity, labor, and machine overhead. Apply a markup of 20–40% for online print-on-demand services where you compete on price, or 50–100% markup for custom local work where you provide a service. Do not overlook labor: if slicing and post-processing takes 45 minutes and your time is worth $20/hour, that is $15 per job that must appear somewhere in your price. Consider platform fees (Etsy takes 6.5%, PayPal/Stripe take ~3%), packaging materials, and shipping time when setting final prices. Many successful print sellers price at 3–5x raw material cost as a rough heuristic, which typically covers all overhead and provides reasonable profit.
What is the formula used to convert filament weight to length?
The formula derives from the geometry of a cylinder: the filament's cross-sectional area multiplied by its length equals the volume. Volume = π × (diameter/2)² × length. Since mass = volume × density, we can solve for length: Length (m) = (mass_g × 4) ÷ (density_g/cm³ × π × diameter_mm²). The factor of 4 in the numerator comes from rearranging π × (d/2)² = π × d²/4, which gives the simplified form. For a 1.75mm PLA filament at 1.24 g/cm³, one gram of filament equals approximately 0.336 meters (33.6 cm). For a full 1 kg PLA spool on 1.75mm filament, this gives approximately 336 meters total. PETG at 1.27 g/cm³ gives slightly less length per gram than PLA because it is denser.