PEI vs PET
How PEI and PET compare, from typical settings across every filament we list.
- PEI is tougher, stiffer, more heat resistant and better outdoors; PET is easier to print.
- PEI typically prints about 125 °C hotter at the nozzle.
- PEI typically prints about 60 °C hotter on the bed.
- PEI is less dense, so a 1 kg spool holds about 17 m more 1.75 mm filament.
- There are 17 PEI filaments in 24 colours, and 17 PET filaments in 79 colours.
At a glance
Our rating, out of 5| PEI | PET | |
|---|---|---|
| Ease of printing | Easier to print | |
| Toughness | Tougher | |
| Stiffness | Stiffer | |
| Heat resistance | More heat resistant | |
| Outdoor and UV | Better outdoors | |
| Flexibility | ||
| Setup | Needs an enclosure, Dry before printing, Needs ventilation | No enclosure or special setup needed |
| PEI | PET | |
|---|---|---|
| Full name | Polyetherimide | Polyethylene terephthalate |
| Filaments listed | 17 | 17 |
| Brands | 10 | 13 |
| Colours | 24 | 79 |
| Nozzle temperature | 340–380 °C | 220–250 °C |
| Bed temperature | 120–160 °C | 70–90 °C |
| Density | 1.27 g/cm³ | 1.34 g/cm³ |
| Length of 1 kg (1.75 mm) | about 327 m | about 310 m |
| Max drying temperature | – | – |
Temperatures are medians across each material's filaments, rounded to 5 °C. Always check the maker's settings for a specific filament.
Brands that make both
3 brands make both PEI and PET.