How Much Laser Power Do You Actually Need?
A practical way to size laser power from production thickness, not from the brochure maximum.
Buyers often anchor on the biggest number in the brochure. That is the wrong starting point. Laser power should be sized from the thickness you cut every week, at the edge quality your customers accept.
The thickness rule
As a planning guide: 1.5-2 kW handles thin sheet and light fabrication; 3 kW covers most mixed job-shop work up to 6-8 mm; 6 kW is the current sweet spot for 1-12 mm production; 12 kW and above is for thick plate and high-volume stainless.
Why maximum thickness misleads
The maximum thickness in a spec sheet is usually an edge case: a slow single cut at a quality nobody would sell. Production thickness is typically 60-70 percent of that figure. Buying for the maximum means paying for power you rarely use.
Power vs speed vs edge
Higher power does not just cut thicker; it cuts faster at the same thickness and improves edge quality at the top end. For shops running 3-6 mm material, a 6 kW machine can beat a 3 kW machine on cost per part because of throughput, not thickness.
For a thickness and speed reference, see the thickness and speed chart.
For background on how fiber sources convert power into a cut, IPG Photonics publishes useful technical material on fiber laser technology.