Spool Weight Calculator
Calculate how much filament remains on your spool by weighing it and entering the values below.
Total weight of new spool with filament
Current weight of your spool
Weight of empty spool (usually 200-300g)
Enter values and click Calculate to see results
How to Use This Calculator
- Weigh your current spool - Place the entire spool on a scale and record the weight in grams
- Find the full spool weight - Check the packaging or manufacturer website (usually 1000g + spool weight for 1kg filament)
- Enter empty spool weight - Most spools weigh 200-300g empty. Check manufacturer specs or weigh an empty spool
- Select filament type - Different materials have different densities
- Calculate - See how much filament you have left
Understanding the Formula
The calculator uses this simple formula:
Remaining Filament (g) = Current Weight - Empty Spool Weight
Approximate Length (m) = Remaining Weight / (Density × π × (Diameter/2)²)
For 1.75mm filament: Length ≈ Weight / (Density × 0.00240)
Common Empty Spool Weights
| Brand | Empty Spool Weight |
|---|---|
| Generic/Budget Spools | 200-250g |
| Bambu Lab | 140-160g |
| Prusament | 200-250g |
| eSun | 200-240g |
| Hatchbox | 230-270g |
Weights are approximate. Weigh an empty spool for accuracy.
Tips for Accurate Measurements
- Use a kitchen scale accurate to at least 1 gram
- Weigh the spool with any dust covers or cardboard holders removed
- Check the manufacturer's specs for exact spool weight
- Save an empty spool from the same brand to weigh for future reference
- Remember that silica gel packets add 5-10g to the weight
Related Tools
- Print Cost Calculator - Calculate cost per print
- Filament Length Calculator - Convert weight to length