Guide
How laser settings work
A laser setting is the combination of values your software sends to the machine for one operation on one material. Most settings come down to how much energy reaches each spot of the material, and how often.
The settings that matter
- Power (%)
- The share of the laser's maximum output used for the job. More power puts more energy into the material: deeper engraving, darker marks, and cuts through thicker stock, but also more charring and a wider kerf. CO2 lasers often take a minimum and a maximum power; the maximum is what matters for most jobs.
- Speed (mm/s)
- How fast the head moves while firing. Slower speeds leave more energy in each spot, so speed and power work as a pair: halving the speed has a similar effect to raising the power. Engraving usually runs much faster than cutting.
- Passes
- How many times the laser repeats the path. Several faster passes often cut thick material more cleanly than one slow pass, with less scorching, especially on diode lasers.
- Line interval, LPI, or density
- For fill engraving, the gap between scan lines. A smaller interval (higher LPI) gives a smoother, darker fill but takes longer. Use the line density converter to move between LPI, lines per centimeter, and millimeters.
- Frequency (kHz) and pulse width (ns)
- Fiber and MOPA lasers fire in pulses. Frequency sets how many pulses per second; on MOPA sources, pulse width (Q-pulse) sets how long each lasts. These change the mark itself, such as deep engraving versus annealing colors on stainless steel.
- Focus and air assist
- A focused beam gives the smallest spot and the most energy density; deliberately defocusing spreads it for softer engraving. Air assist clears smoke and reduces flare-ups and charring, and it matters most when cutting.
Cut, score, and engrave
- Cut: a vector line run slowly at high power to go all the way through. Thickness drives the number of passes.
- Score: the same vector path at lower power or higher speed, marking the surface without cutting through.
- Engrave: a raster fill scanned line by line, where line interval matters as much as speed and power.
Settings by laser type
- Diode lasers
- Blue diode modules (commonly 5–40W optical) engrave wood, leather, and coated metals well and cut thin wood and dark acrylic. They cannot cut clear acrylic, which the blue wavelength passes through.
- CO2 lasers
- The workhorse for cutting wood, acrylic, leather, paper, and fabric. CO2 marks glass and stone well and removes the coating on anodized aluminum, but bare metal needs a marking spray.
- Fiber and MOPA lasers
- Galvo lasers built for metals and some plastics. Settings revolve around speed, power, frequency, and (on MOPA) pulse width, and line interval is often much finer than on gantry machines.
- UV lasers
- Short-wavelength lasers that mark with very little heat: glass, plastics, and delicate materials. Settings are usually very specific to the source and lens.
Not sure which type fits your work? See the laser selection guide.
How to dial in a new material
- Start from a setting for your exact machine and wattage, not just the same laser type.
- Run a small test grid on scrap from the same sheet, varying speed in one direction and power in the other.
- Pick the square that looks right, then test it on a small piece of the real design.
- Save the result with the material, thickness, and machine so you never have to test it again.
Laser settings FAQ
What are the best laser settings for wood, acrylic, or leather?
There is no single best setting for a material. The right speed and power depend on your laser type, its wattage, the lens and spot size, the exact material, and its thickness. Start from a setting shared for the same machine and wattage, then run a small test grid on scrap from the same sheet before the full job.
Why don't laser settings from another machine work on mine?
Power percentages are relative to each machine's own tube or module, so 50% on a 10W diode and 50% on a 60W CO2 laser are very different amounts of energy. Spot size, focus, mirror alignment, air assist, and tube age also vary between machines, even of the same model. Settings for the same machine model are the closest starting point.
How do I convert mm/min to mm/s?
Divide by 60. 6,000 mm/min equals 100 mm/s. Settings on The Laser Workshop are shown in mm/s.
What is the difference between LPI and line interval?
Both describe how close together engraving lines are. LPI (lines per inch) counts lines in an inch; line interval is the gap between lines in millimeters. Interval in mm equals 25.4 divided by the LPI, so 254 LPI is a 0.1 mm interval. Some software uses lines per centimeter instead.
Which materials should never be laser cut?
Never laser PVC, vinyl, or other chlorine-containing plastics: they release chlorine gas that is harmful to people and corrodes the machine. Also avoid polycarbonate (it burns rather than cuts) and any material you cannot identify. Check the material's safety data sheet when in doubt.
How do I share my own laser settings?
Create a free account, save the material in your settings library with the machine you used, and mark it public. It then appears in the community library and on the page for your machine.