What first layer height should I use?

A good starting point is 75% of your nozzle diameter. For a 0.4mm nozzle, that is 0.3mm. This gives enough squish for adhesion without being so thin that it struggles to extrude evenly.

Why is the first layer wider than normal?

A wider first layer (typically 120% of nozzle diameter) increases the contact area with the bed. More contact means better adhesion and a more stable foundation for the rest of the print.

Should I print the first layer slower?

Yes. Printing the first layer at 15-25mm/s gives the filament more time to bond with the bed surface. Faster speeds increase the risk of the first layer peeling up or not sticking properly.

How do Z-offset and flow rate affect the first layer?

Z-offset sets the nozzle-to-bed gap. A negative Z-offset lowers the nozzle so the layer is "squished" into the bed for better adhesion (the calculator shows this as the nozzle gap = layer height + Z-offset). Flow rate is a volumetric extrusion multiplier: with the gap fixed by Z, extra flow does not raise the layer, it widens the deposited bead. The calculator shows the resulting deposited width at your chosen flow.

Does the first layer need a different nozzle temperature?

It depends on the material. PLA prints the first layer about 5°C hotter (215°C vs 210°C) to bite into the bed. PETG is the opposite — the first layer is run cooler (around 230°C) to avoid the nozzle dragging molten plastic. The calculator applies the right per-material adjustment automatically.

3DPrintCalcs

First Layer Settings Calculator

Optimise first layer height, width, temperature and speed for strong bed adhesion.

Nozzle SizeYour installed nozzle diameter — first layer height is set to ~75% of this and width to ~120%

MaterialFilament type — sets the recommended bed/nozzle temps, first-layer temperature delta and slow first-layer speed

Bed SurfaceBuild plate type — tweaks bed temp and gives an adhesion tip (glass usually needs glue/hairspray, PEI sticks well clean)

How We Calculate This

Calculations

First layer height = Nozzle diameter × 0.75
First layer width = Nozzle diameter × 1.20
Bed temperature = Material base + Surface adjustment
Nozzle temperature = Other-layers base + per-material first-layer delta (PLA +5°C, PETG -10°C, ABS +5°C, TPU 0)
Speed = 20mm/s base × Material speed factor
Nozzle gap = First layer height + Z-offset (a negative Z-offset shrinks the gap for more squish)
Deposited width = First layer width × Flow rate (flow adds plastic to the bead, it does not raise the layer)

Z-offset changes the geometric nozzle-to-bed gap, while flow rate is a volumetric multiplier that widens the deposited bead at a fixed gap. These are shown separately because they act on different things.

Frequently Asked Questions

Related Calculators

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Estimate the contact area and adhesion force for your print footprint.

Brim Width Calculator

Calculate optimal brim width based on part footprint and material shrinkage.

Raft Calculator

Estimate extra material and time for raft adhesion layers.

Last updated: March 2026

All calculations are estimates. Always verify settings with test prints before committing to final prints.