Spool remaining filament calculator
Put the spool on a kitchen scale, pick your spool brand, and see exactly how much filament is left — in grams, meters, and money. Wet spool? Check the drying times first; need grams for a given meter count, use the filament length to weight calculator.
0 g
filament left on the spool
| Length remaining | 0 m |
| Share of spool | 0% |
| Value remaining | €0.00 |
| Enough for the print? | – |
Estimate only — tare weights vary by batch and spool revision. For an exact number, weigh an empty spool of the same brand and use the custom tare field, or calibrate the tare from a fresh full spool below.
Weigh a fresh spool
No empty spool at hand? Put a new, full spool on the scale and subtract the labeled net weight — that is the exact tare of that spool revision, QR-code sticker or not.
Exact tare: 250 g
How it works
The scale reads spool + filament, so remaining = scale − tare. The tare presets are a community consensus of typical empty-spool weights (compiled by spool trackers such as filamiq and sigmafilament) — cardboard spools are light (~140 g), plastic ones heavy (up to ~250 g). Meters are derived from the material density and strand cross-section, exactly as in the filament length to weight calculator. The value line prices the remainder at your per-spool price — the filament cost calculator does the same per print.
Frequently asked questions
How do I know how much filament is left on my spool?
Put the whole spool on a kitchen scale, subtract the empty-spool weight (the tare), and the rest is filament. The calculator turns that into grams, meters, percentage and value.
How much does an empty filament spool weigh?
Cardboard spools are around 140 g, plastic ones up to roughly 250 g. The presets list typical tares per brand; for an exact number, weigh an empty spool of the same brand and enter it as a custom tare — or weigh a fresh full spool and subtract the labeled net weight (the "Weigh a fresh spool" section does the math).
How accurate is the estimate?
Only as accurate as the tare — spool weights vary by batch and revision, sometimes by tens of grams. Treat the result as an estimate and keep a safety margin before starting a long print.
What does the "enough for this print?" check compare against?
The grams or meters your slicer reports for the job, plus a headroom percentage (default 5%) to cover purge lines and priming. It answers yes or no with the surplus or shortfall, but it cannot predict failed prints — leave extra margin for risky jobs.