3D Printing Layer Height Guide
Layer height is one of the most impactful settings in FDM printing. It controls print quality, surface finish, and how long the print takes.
Last updated: May 2026
The 25-75% rule
Layer height must stay between 25% and 75% of your nozzle diameter. Below 25% and the nozzle can't extrude reliably; above 75% and layers don't bond well, leaving a weak and visibly rough print. For the most common 0.4 mm nozzle, that means layer heights between 0.1 mm and 0.3 mm.
Most slicers default to 0.2 mm with a 0.4 mm nozzle, exactly 50% of the nozzle diameter. That's a safe starting point for general-purpose prints.
Layer height by nozzle size
| Nozzle | Detail (slow) | Standard | Draft (fast) | Max usable |
|---|---|---|---|---|
| 0.2 mm | 0.05 mm | 0.1 mm | 0.15 mm | 0.15 mm |
| 0.25 mm | 0.06 mm | 0.12 mm | 0.18 mm | 0.18 mm |
| 0.4 mm | 0.1 mm | 0.2 mm | 0.28 mm | 0.3 mm |
| 0.6 mm | 0.15 mm | 0.3 mm | 0.4 mm | 0.45 mm |
| 0.8 mm | 0.2 mm | 0.4 mm | 0.55 mm | 0.6 mm |
| 1.0 mm | 0.25 mm | 0.5 mm | 0.65 mm | 0.75 mm |
Quality vs speed
Lower layer heights produce smoother surfaces and finer detail because each layer is thinner and the staircase effect is smaller. The trade-off is time: halving the layer height roughly doubles print time, because the printer must make twice as many passes.
- 0.05-0.1 mm: Miniatures, jewelry, parts where surface finish matters more than time
- 0.15-0.2 mm: Standard quality for most everyday prints, the default on most slicers
- 0.25-0.3 mm: Draft and prototyping, faster, slightly rougher surfaces, still structurally sound
- Above 0.3 mm (0.4 mm nozzle): Not recommended, layers don't bond reliably and surfaces look coarse
First layer height
The first layer is usually set independently and is often thicker than the rest, typically 0.2-0.3 mm regardless of the main layer height. A thicker first layer helps the print stick to the bed and compensates for minor bed levelling variations. Many slicers set this automatically at 100-150% of the standard layer height.
Variable layer height
Most modern slicers (PrusaSlicer, OrcaSlicer, Cura) support variable or adaptive layer height, where the slicer automatically adjusts layer height in different regions of the model. Flat surfaces get thick layers for speed; curved or detailed areas get thin layers for quality. This is one of the best ways to reduce print time without sacrificing visible quality.
Layer height is the second link in the calibration chain
The 75%-of-nozzle ceiling is not a guideline you can negotiate: it is a physical constraint imposed by the nozzle you already chose. That number must be confirmed before this page means anything, and every step after this one inherits the layer height you settle on here. Follow the chain in order:
- Nozzle diameter first. Everything this page contains is relative to that one dimension. The nozzle diameter decision guide walks the trade-offs, the nozzle size chart shows flow rates, and the nozzle size comparison puts the options side by side.
- You are here. Layer height. The ceiling is 75% of nozzle diameter; cross it and layer adhesion fails. The table above maps that ceiling to every common nozzle. How far below the ceiling you go determines surface quality and print time in opposite directions: 50% is a neutral starting point, closer to 25% buys detail, closer to 75% buys speed.
- Extrusion width next. A well-tuned line width runs between 100% and 120% of nozzle diameter, but the right value depends on your layer height too. Feed both numbers into the extrusion width calculator to get a value the slicer will actually honour.
- Volumetric flow is what makes or breaks the combination. Multiply layer height by line width by target speed: that product must stay under the hotend's throughput limit or the extruder will lose ground on every fast move. Use the volumetric flow calculator before you commit to a print speed.
- Codify the numbers in a slicer profile. A profile is what stops accidental overrides from undoing this calibration on the next job. How Bambu Studio stores and applies these values is covered in what Bambu Studio presets actually change.
- When surface quality drops unexpectedly, resist the reflex to lower layer height. Underextrusion mimics layer-height problems almost exactly. The underextrusion guide separates the two causes so you fix the right one.
Material changes the calculus too. With TPU I stay at 0.2 mm layers or thicker on all three of my machines: thin flexible layers are where the Ender 3's Bowden setup starts skipping, and while the direct-drive Bambu machines handle it better, the extra print time rarely pays off. For rigid PLA and PETG the layer height is a free choice; for TPU it is half decided by the extruder you are printing on.
Frequently Asked Questions
What layer height should I use with a 0.4 mm nozzle?
0.2 mm is the standard starting point, it's 50% of the nozzle diameter and gives a good balance of quality and speed. Use 0.1 mm for detailed or decorative prints, or 0.28-0.3 mm when you want a faster draft print and surface finish is less important.
Does a lower layer height always give better quality?
For surface smoothness, yes, thinner layers reduce the staircase effect on curved surfaces. But going too low (below 25% of nozzle diameter) risks poor extrusion consistency and can actually produce worse results. Below 0.1 mm with a 0.4 mm nozzle, most printers struggle to extrude reliably enough to benefit.
What layer height is best for printing miniatures?
0.05-0.1 mm with a 0.2 mm or 0.25 mm nozzle. A smaller nozzle is the bigger factor, it allows finer features that a 0.4 mm nozzle simply can't form, regardless of layer height. At 0.05 mm layer height and 0.2 mm nozzle, prints can reach a level of detail that rivals resin for many purposes.
Why do some slicers set the first layer differently?
The first layer needs to adhere firmly to the build plate and tolerate small bed levelling errors. A thicker first layer (often 0.2-0.3 mm, sometimes 100-150% of the standard height) squishes more plastic into the surface and creates a wider contact area. After the first layer, the slicer switches to the configured layer height.
Does layer height affect print strength?
Yes, but not in the direction most people expect. Very thin layers (0.05-0.1 mm) can sometimes be weaker in the Z direction because there are more layer interfaces, each a potential delamination point. Mid-range layer heights (0.2-0.3 mm) often produce stronger parts because each layer bonds over a larger area. Strength is also heavily influenced by infill percentage and wall count.