3D Printing Calculators
Twelve calculators for cost, filament, calibration and printer settings. Results appear as you type, free and without signing up.
Print cost
Work out what one print costs you, then a selling price with your own markup.
- Filament
- Electricity
- Machine wear
- Failure allowance
- Cost per print
- Selling price
- Profit
How it works: filament = price/kg × grams ÷ 1000; electricity = watts ÷ 1000 × hours × price per kWh; wear = rate/h × hours. Cost = the sum ÷ (1 − failure rate), because every failed print is printed again. Selling price = cost × (1 + markup). Dollar values use the shop's exchange rate of today (estimate).
Filament length ↔ weight
Fill in metres or grams; the other one follows.
- Weight per metre
- Metres per kg
- Result
How it works: weight (g) = π × (diameter ÷ 2)² × length (mm) × density ÷ 1000. Example, 1.75 mm PLA: about 2.98 g per metre, about 335 m per kg.
Filament left on a spool
Weigh the spool with its filament, then take off the weight of the empty spool.
- Filament left
- Length left
- Of a 1 kg spool
| Spool type | Estimate | Usual range |
|---|---|---|
| Plastic 1 kg spool (common) | ±220 g | 180–260 g |
| Cardboard 1 kg spool | ±150 g | 130–170 g |
| Plastic 0.5 kg spool | ±130 g | 100–160 g |
| Mini 250 g spool | ±70 g | 50–90 g |
| Plastic 3 kg spool | ±600 g | 500–750 g |
| Refill without spool (your own spool) | 0 g | 0 g |
How it works: left (g) = weight on the scale − empty spool weight; left (m) = left (g) ÷ weight per metre (see the length ↔ weight calculator).
Filament drying guide
Filament that has taken up moisture strings, pops and prints brittle. Pick the material and the tool:
- Temperature
- Time
- Note
| Material | Air temperature | Time |
|---|---|---|
| PLA | 45–50 °C | 4–6 h |
| PETG | 60–65 °C | 4–6 h |
| ABS | 65–80 °C | 4–6 h |
| ASA | 65–80 °C | 4–6 h |
| TPU | 50–55 °C | 4–8 h |
| Nylon (PA) | 70–80 °C | 8–12 h |
| PC | 70–80 °C | 6–8 h |
| PLA-CF | 50–55 °C | 6–8 h |
| PETG-CF | 60–65 °C | 6–8 h |
How it works: dryer boxes and dehydrators use the air temperature in the table. On a printer bed the air inside the box stays cooler than the bed, so the bed is set about 10 °C higher and the time is about 1.5×. Plastic spools can soften above about 60–70 °C; check the spool for high temperatures.
Material shrinkage
Plastic shrinks a little as it cools. For parts that must fit, scale them up in the slicer.
- Shrinkage used
- Slicer scale
- Model size
How it works: scale = 100 % ÷ (1 − shrinkage). From a test print: shrinkage = (model size − measured size) ÷ model size. Model size = wanted size × scale.
Rough print time
A rough estimate before you open a slicer. The slicer is always more exact.
- Extruded plastic
- Weight (PLA)
- Rough print time
How it works: plastic = volume × (0.45 + 0.55 × infill): about 45 % of the volume is taken as solid walls, top and bottom. Time = plastic ÷ (layer × line width × speed × 0.5); the 0.5 covers travel, slowing in corners and layer changes. A rough estimate only.
E-steps calibration
Mark the filament 120 mm above the extruder, extrude 100 mm (slowly, hot nozzle), then measure how much really went in.
- New e-steps
- Change
- G-code
How it works: new e-steps = current e-steps × requested length ÷ length extruded. Example: 93 × 100 ÷ 97.5 = 95.38. Save with M92, then M500.
Flow rate calibration (wall thickness)
Print a hollow cube with no top and no infill, then measure its wall with calipers on several sides.
- Expected thickness
- New flow
How it works: expected thickness = line width × wall count; new flow = current flow × expected ÷ measured. Calibrate e-steps first.
Volumetric flow (mm³/s)
A hotend can only melt so much plastic per second. Above that limit prints come out under-extruded.
- Flow
- Hotend limit (typical, PLA)
- Top speed at that limit
- Status
How it works: flow = layer height × line width × speed. The hotend limits are typical values for PLA; PETG, ABS and TPU are usually lower, and a hotter nozzle raises them a little.
Magic layer heights
A layer height that matches whole full steps of the Z motor makes every layer equally thick.
- One full step
- Nearest to your choice
Recommended layer heights (0.04–0.40 mm):
How it works: one full step = lead × step angle ÷ 360 (or microstepping ÷ steps/mm). Good layer heights are multiples of that full step. Example: 8 mm lead, 1.8° motor → 0.04 mm, so 0.12 / 0.16 / 0.20 mm.
Stepper driver Vref
For drivers set with a trimpot. In UART/SPI mode the current is set in the firmware instead.
- Target current
- Vref
How it works: TMC2209/2208: Vref = I(rms) × 2.5 × √2 × (Rsense + 0.02) ÷ 0.325 (with Rsense 0.11 Ω: Vref ≈ 1.41 × I). A4988: Vref = I × 8 × Rsense. DRV8825: Vref = I × 5 × Rsense. Measure Vref between the trimpot and GND, printer on, motors idle.
Acceleration distance
How far does the print head travel before it reaches full speed? On short lines a high speed is never reached.
- Distance to full speed
- Time to full speed
- Shortest line (up + down)
- Top speed on that line
How it works: distance = v² ÷ (2 × a); time = v ÷ a. Slowing down takes the same distance, so a line needs ≥ 2 × that distance to reach v. On a shorter line the peak speed = √(a × length).
Frequently asked questions
How many metres of filament are in 1 kg?
For 1.75 mm PLA about 330–335 metres (density 1.24 g/cm³). PETG is a little shorter (about 325 m), ABS longer (about 400 m) because it is lighter.
How do I work out the cost of a 3D print?
Add the filament (price per kg × grams ÷ 1000), the electricity (watts ÷ 1000 × hours × price per kWh) and the machine wear per hour, then add an allowance for failed prints.
When should I calibrate e-steps?
After changing the extruder, its gears or the firmware, or when every print looks under- or over-extruded. Calibrate e-steps first, then the flow rate.
What temperature dries PLA filament?
Typically 45–50 °C for 4–6 hours. Stay below about 55 °C, where PLA starts to soften.
Rather not print it yourself? We print it for you.
Send your STL/3MF file or design your own in our online designers; we print and ship it.