Comparison · Lasers
Diode vs CO2 vs Fiber Laser Engravers: Which Type Fits Your Work?
"Laser engraver" covers three very different machines. Diode, CO2 and fiber lasers produce light at different wavelengths, and wavelength decides which materials absorb the beam. That is why one laser cuts clear acrylic easily, another can't touch it, and a third marks steel but struggles with wood.
This guide explains the differences in practical terms so you can match the laser type to your materials before comparing individual machines. For safety basics that apply to all three, read the manufacturer's manual and make sure any eyewear is rated for your specific wavelength.
Why wavelength matters
A laser only does work on a material if that material absorbs its light. Different materials absorb different wavelengths. Clear acrylic, for example, lets visible blue light pass through but absorbs far-infrared light strongly. Bare metals reflect much of the far-infrared light from a CO2 laser but absorb near-infrared light from a fiber laser well enough to mark.
| Type | Typical wavelength | Light type |
|---|---|---|
| Blue diode | Roughly 440–460 nm | Visible blue |
| CO2 | About 10,600 nm (10.6 µm) | Far infrared, invisible |
| Fiber | Around 1,064 nm | Near infrared, invisible |
Some diode machines use infrared modules instead of blue, and some systems combine modules. Check the exact wavelength in any machine's specifications.
What each type does well
The table below shows general tendencies. Results depend on power, optics, settings and the specific material, so test on scrap and check the manufacturer's material guidance.
| Material | Diode | CO2 | Fiber |
|---|---|---|---|
| Wood and plywood (engrave) | Good | Very good | Limited |
| Wood and plywood (cut) | Thin stock, multiple passes | Good, thicker stock | Not suited |
| Leather (vegetable-tanned) | Good | Very good | Limited |
| Paper and cardboard | Good | Very good | Limited |
| Clear acrylic | Poor; beam passes through | Very good, clean polished edges | Poor |
| Dark or opaque acrylic | Possible on some colors | Very good | Limited |
| Glass (surface etch) | Limited, usually needs coating | Common | Limited |
| Anodized aluminum (mark) | Often possible | Often possible | Very good |
| Bare steel and other metals (mark) | Needs marking spray or coating | Needs marking compound | Very good |
| Cutting metal | No | Not on hobby machines | Thin foil or deep engraving at most on marking machines |
Diode lasers
Diode engravers are usually open-frame gantries with a laser module on the carriage, similar in layout to a small CNC router. They're the most common entry point for hobby use.
- Strengths: compact, light, quiet apart from fans, often simpler to set up, and can come with large work areas for the size. Many are compatible with common laser software.
- Limits: slower cutting than CO2, limited cutting thickness, poor on clear and many light-colored materials, and metal marking usually needs a coating.
- Read the power spec carefully. Some listings quote electrical input power, others quote optical output power. Optical output is the number that relates to performance; look for it explicitly.
- Enclosure: most open-frame diodes need an add-on enclosure for fume capture and to contain reflections.
Browse diode laser engravers on Amazon
CO2 lasers
CO2 machines use a gas-filled tube (glass or metal RF types) and a set of mirrors to steer the beam to the head. Many hobby and small-business CO2 lasers are enclosed cabinets with a lid.
- Strengths: versatile across wood, acrylic (including clear), leather, paper, fabric and glass etching. Faster cutting than a comparable diode on many materials.
- Limits: larger and heavier, more involved setup, mirror alignment, and the tube is a consumable with a finite life. Doesn't directly mark bare metal.
- Cooling: glass-tube machines need water cooling, either a pump and reservoir or a dedicated chiller. Running without proper cooling can damage the tube.
- Exhaust: requires real ventilation, typically ducted outside or to a fume filter.
Browse CO2 laser chillers on Amazon
Fiber lasers
Hobby and small-business fiber lasers are usually galvo machines: the head stays still and fast-moving mirrors steer the beam across a small field. They're built for marking and engraving, especially metals.
- Strengths: fast, high-detail marking on steel, aluminum, brass and many coated or anodized parts; deep engraving with multiple passes; low maintenance compared with CO2.
- Limits: small work field compared with gantry machines, poor on wood and clear materials, and not a tool for cutting sheet stock.
- Safety: the beam is invisible near-infrared light. Eyewear must be rated for the fiber laser's wavelength, and an enclosure is strongly advisable.
Some workshops add a fiber laser alongside a CO2 or diode machine rather than choosing between them, because the material ranges barely overlap.
Gantry vs galvo motion
Gantry
The head moves on X and Y axes. Larger work areas, can cut sheet stock, slower engraving. Typical for diode and CO2.
Galvo
Mirrors move the beam. Very fast marking within a small field set by the lens. Typical for fiber; some CO2 and diode galvos exist.
If you want to cut parts from sheets, you want a gantry. If you want to mark many small items quickly, a galvo is the better fit.
Space, upkeep and running costs
The purchase price is only part of the picture. Each type has its own ongoing needs, and those often decide which one fits your home or shop.
| Factor | Diode | CO2 | Fiber |
|---|---|---|---|
| Footprint | Compact frame; enclosure adds size | Usually a larger cabinet plus cooling and exhaust | Compact benchtop unit |
| Cooling | Fans on the module | Water cooling for glass tubes; check RF tube requirements | Typically air-cooled |
| Consumables | Lens or protective window; module eventually | Tube, mirrors and lens need cleaning and eventual replacement | Lens protection; relatively low upkeep |
| Alignment | Focus height only | Mirror alignment needed periodically | Focus height; galvo field calibration |
| Ventilation | Required | Required | Required, especially for coated metals and plastics |
Check the manufacturer's maintenance schedule and the availability and current price of replacement parts, especially CO2 tubes and diode modules, before buying. A machine with easily sourced parts is cheaper to own over time.
How to choose
- Mostly wood, leather, cardboard, budget-conscious, limited space → diode.
- Acrylic (especially clear), faster cutting, broad material range, room for a cabinet and cooling → CO2.
- Metal marking, tumblers, tags, tools, jewelry → fiber.
- Want to cut thick wood or make joinery → consider a CNC router instead of, or alongside, a laser.
Questions for any listing
- What is the wavelength and optical output power?
- What is the work area, and does it allow pass-through?
- Does it include an enclosure, exhaust, air assist and, for CO2, cooling?
- What safety features are included: e-stop, lid interlock, flame detection?
- What software does it support, and what are the current license terms?
- Are replacement parts (lenses, tubes, modules) available?
Browse laser air assist pumps on Amazon
FAQ
Can a diode laser cut clear acrylic?
Generally not well. Clear acrylic lets visible blue light pass through instead of absorbing it. Some dark or opaque acrylics can be cut or engraved with a diode. CO2 lasers handle clear acrylic well.
Can a CO2 laser engrave metal?
Not bare metal directly in most hobby setups, because metals reflect its far-infrared light. It can mark anodized or coated metals, and with a marking compound it can leave a mark on bare metal. Fiber lasers mark bare metals directly.
Is a fiber laser good for wood?
It's not the right tool for most wood work. Fiber lasers are designed for metals and some plastics; a diode or CO2 laser is better for wood.
What does laser power in a listing mean?
It may be electrical input power or optical output power. Optical output is what relates to cutting and engraving ability, so check which figure the listing uses.
Do all laser types need eye protection?
Yes. Eyewear must be rated for your laser's specific wavelength, or the machine must be fully enclosed with a viewing window rated for that wavelength. Follow the manufacturer's safety guidance.
Bottom line
Choose by material. Diodes are a sensible, compact start for wood and leather. CO2 is the versatile choice for acrylic and cutting a broad range of organics, at the cost of size, cooling and upkeep. Fiber is the specialist for metal marking. Whichever you pick, budget for an enclosure, exhaust and eyewear rated for the exact wavelength, and confirm specs like optical power and included safety features directly with the manufacturer.