Weight ↔ length ↔ cost. Estimate remaining filament by spool weight or dimensions. Everything runs locally, ad-free.
If “Net grams” is empty, we’ll use gross − empty. Leave these blank if you prefer the dimensions method below.
If “Net grams” and “Gross/Empty” are blank, we’ll estimate remaining length from spool dimensions using k·π·W·(Do²−Di²)/(4·A).
Assumes round, solid filament and constant density. CF-filled materials vary by brand — adjust density if known.
For volume-based estimates we use mass = ρ · volume. For length-based, we use g per metre. Both include your safety margin.
A few common questions about how this 3D printing filament calculator works, what it assumes, and how to get the most reliable estimates.
No. You can use whichever method is easiest for you:
If you provide net grams or gross/empty weights, the app will prioritise that. If those are blank, it falls back to the dimensions method to estimate remaining filament length.
The packing factor describes how tightly the filament is wound. A value of 0.90
is a reasonable default for neatly wound spools. If your filament is loosely wound or very messy,
you may want to reduce it (e.g. 0.80–0.85) to avoid over-estimating remaining length.
The preset densities for PLA, PETG, ABS, ASA, Nylon, TPU, PC and CF blends are typical values taken from manufacturer data sheets and community averages. Individual brands and colours can vary slightly, so if you have a data sheet for your exact filament, you can switch to Custom and paste the manufacturer’s density value in the ρ field.
The safety margin accounts for real-world inefficiencies: priming, purging, test lines, small calibration pieces and slicer rounding. Leaving the default 10% margin reduces the risk of a long print failing because the spool runs out a few metres short.
No. This is a simple, ad-free browser app. All calculations are performed locally in your browser using vanilla JavaScript, and no usage data or spool details are sent to a server or analytics platform.