Quick answer
Polycarbonate (PC) is generally the stronger, more impact-resistant and more heat-tolerant material, while PETG is cheaper and much easier to print. For most hobby parts, PETG is enough. Reach for polycarbonate when a part has to survive hotter conditions or harder knocks and you have a printer capable of the higher temperatures it needs.
Properties differ between brands and blends (many “PC” filaments are blends designed to print more easily), so use the manufacturer’s datasheet for real numbers.
Comparison table
| Property | PETG | Polycarbonate |
|---|---|---|
| Printing difficulty | Easy to moderate | Moderate to difficult |
| Impact resistance | Good | Generally higher |
| Heat resistance | Moderate | Generally higher |
| Nozzle temperature | Roughly 230-250 C | Often 260 C and above, sometimes much more |
| Enclosure | Usually not needed | Often recommended |
| Warping | Low | Moderate to high |
| Moisture sensitivity | Moderate | High |
| Cost | Lower | Higher |
Strength and impact resistance
Polycarbonate is well known as a tough material used in safety glazing and protective equipment in sheet form, and printed PC is typically regarded as more impact-resistant than PETG. PETG is still a durable, practical choice and is much tougher than acrylic in sheet form, but it is usually described as moderate rather than extreme in impact resistance. Printed parts behave differently from molded or extruded sheet because of layer lines, so do not assume sheet performance carries over directly. The impact strength comparison of plastics puts both materials alongside others.
Heat resistance
This is often the deciding factor. PETG begins to soften at a relatively low temperature and can sag in a hot car or near a heater. Polycarbonate usually holds up at noticeably higher temperatures. If you need a printed part near heat, check the specific filament’s heat deflection or glass transition figures rather than relying on a general comparison.
Printing difficulty
PETG prints on most machines with a heated bed and a standard hotend. Expect some stringing and strong adhesion to certain build surfaces.
Polycarbonate typically needs:
- A hotend rated for higher temperatures (check that your hotend and PTFE parts are suitable).
- A hot bed and a suitable adhesive.
- An enclosure in many cases, to reduce warping and layer splitting.
- Dry filament, since PC absorbs moisture.
Blends marketed as easier PC can lower these demands. Higher temperatures also mean more caution: make sure your printer is rated for the temperatures you plan to use and keep the area ventilated.
Clarity, UV and chemicals
Both can be transparent or translucent in the right form, but printed parts are rarely fully clear because of layer lines. PETG is generally regarded as having good chemical resistance and is often used where cleaning agents are involved. Standard polycarbonate can yellow with prolonged sun exposure unless it is UV-stabilized or coated, and it can be sensitive to some solvents. For outdoor use, look for a UV-resistant grade of either material.
Cost
PETG is typically less expensive and widely available. Polycarbonate filament costs more, and you may also need an upgraded hotend or enclosure.
Which to choose
- PETG: covers, brackets, containers, light-duty mechanical parts, and anything where easy printing matters.
- Polycarbonate: heat-exposed parts, tougher mechanical parts, and designs that see impacts, if your printer can handle it.
- If your priority is wear and flexing rather than heat, see our PETG vs nylon comparison.
FAQ
What does PETG stand for?
Polyethylene terephthalate glycol-modified. The glycol modification changes how the plastic crystallizes, which makes it easier to process and tougher than plain PET.
Is Lexan the same as polycarbonate?
Lexan is a brand name for polycarbonate products. The underlying material is polycarbonate, though specific grades and additives vary.
Is PETG more transparent than PLA?
Natural PETG is often described as clearer than PLA, though printed parts are usually translucent rather than perfectly clear. Printing settings and layer height affect the result.
Is PETG okay to drink out of?
PETG as a raw plastic is used for some food-contact products, but a 3D printed part is a different matter. Layer lines can harbor bacteria, and filament additives, colorants and printer components may not be food-safe. If food contact matters, look for filament explicitly rated for it and treat printed items as single-use or non-drinking vessels unless the manufacturer says otherwise.
How does PETG compare with other plastics?
See our PVC vs PETG guide.