How Power Affects Fiber Laser Marking

Before we break down each wattage, let’s clear up what “power” actually does in a fiber laser system.

Laser power (wattage) determines three things:

But here’s what most buyers miss: marking speed and engraving depth are not the same thing. You can mark a QR code on stainless steel at 7,000 mm/s with a 20W laser. That’s surface-level annealing — fast and efficient. But if you need to engrave a 0.5 mm deep part number into tool steel, the same 20W laser slows to a crawl, requiring multiple passes that eat time.

That distinction — surface marking vs. deep engraving — is the single most important factor in choosing your power level.