This comparison is less about which material is better and more about whether the part should be rigid or compliant. PLA holds its shape, takes fine detail and prints quickly. TPU is a flexible thermoplastic used for bumpers, grips, seals and other parts that need to give under load and spring back.
Numbers come from one supplier, Polymaker, using PolyLite PLA and PolyFlex TPU95 (a Shore 95A grade). Note that the two data sheets use different tensile standards, ISO 527 for the PLA and ISO 37 for the TPU, because rigid plastics and elastomers are tested differently. Prusa's guides add printing advice. Flexible filaments vary widely by hardness, so softer grades will behave differently from the one shown here.
PLA and TPU / flexible filament side by side
| Property | PLA | TPU / flexible filament |
|---|---|---|
| Nozzle temperature | 190–230 °C (PolyLite PLA); Prusa: 215 °C first layer, 210 °C after | 210–230 °C (PolyFlex TPU95); Prusa: 230–245 °C for flexible filaments |
| Bed temperature | 25–60 °C (PolyLite PLA); Prusa: 60 °C | 25–60 °C (PolyFlex TPU95); Prusa: 60–75 °C |
| Print speed | 50–200 mm/s (Polymaker) | 30–50 mm/s (Polymaker); Prusa: about 20 mm/s typical, 30–40 mm/s maximum |
| Retraction | 1–3 mm at 20–40 mm/s (Polymaker) | 3–6 mm at 40–60 mm/s (Polymaker); Prusa: use low retraction or start with none |
| Hardness | Not stated | Shore 95A (PolyFlex TPU95); Prusa: TPU typically about 60A–90A |
| Tensile modulus | 3426.9 MPa X-Y (ISO 527) | 33.6 MPa X-Y (ISO 37) |
| Elongation at break | 6.3% X-Y (ISO 527) | 551.2% X-Y (ISO 37) |
| Heat deflection, ISO 75 (1.8 MPa) | 58 °C | Not stated |
| Feed path | Not stated | Prusa: loosen the extruder idler; the XL needs a flex bypass |
| Drying | 55 °C for 6 h (Polymaker); Prusa lists 45 °C for 6 h for Prusament PLA | 70 °C for 8 h (Polymaker); Prusa lists 60 °C for 4–6 h for Prusament TPU |
| Typical uses | Prusa: concept models, prototypes, figures, simple toys | Prusa: washers, stamps, RC tires, shoe soles, belts, hoses |
Property values come from Polymaker's PolyLite PLA (ISO 527) and PolyFlex TPU95 (ISO 37) technical data sheets, with printing guidance from Prusa's PLA, flexible materials and drying articles.
Rigid versus flexible
The stiffness gap is about a hundredfold. Polymaker lists a tensile modulus of about 3,427 MPa for PolyLite PLA and 33.6 MPa for PolyFlex TPU95. PLA breaks at 6.3% elongation in-plane, while the TPU stretches to 551% before breaking. Because the PLA is tested under ISO 527 and the TPU under ISO 37, read these as an indication of scale rather than a precise ratio.
Hardness is the more useful number when choosing among flexible grades. PolyFlex TPU95 is listed at Shore 95A. Prusa says TPU filaments typically range from about 60A to 90A and that softer filaments are harder to print.
Printing speed and feeding
PLA prints fast and forgives most feed paths; Polymaker lists 50 to 200 mm/s. Flexible filament is slower. Polymaker suggests 30 to 50 mm/s for PolyFlex TPU95, and Prusa suggests about 20 mm/s, with 30 to 40 mm/s as a maximum, because faster printing raises the risk of clogs and tangles.
TPU also needs a gentle feed path. Prusa recommends loosening the extruder idler on its MK-series printers so the gears do not tangle the filament, a bypass print for the XL's long path, and low or no retraction to start. Polymaker lists 3 to 6 mm of retraction for its grade, so tune from the profile for your machine.
Toughness and wear
Prusa describes flexible materials as very resistant to abrasion, with excellent tenacity, low shrinkage and good chemical resistance. That suits bumpers, grips and parts that take repeated impacts. Prusa describes PLA as brittle, breaking along layers or into shards on impact.
TPU has drawbacks. Prusa lists poor bridging and overhangs, difficult support removal, stringing and slow printing. For TPU supports, Prusa suggests a larger Z gap of about 0.3 mm and at least 100% XY separation.
Heat and moisture
Polymaker lists a heat deflection temperature of 58 °C for PolyLite PLA, and Prusa says PLA softens above about 60 °C. Neither the PolyFlex TPU95 data sheet nor Prusa's flexible materials guide gives a heat figure for TPU, so check the exact grade if the part will run warm.
Prusa notes that flexible filaments are hygroscopic and that wet filament is much harder to print. Polymaker recommends drying PolyFlex TPU95 at 70 °C for 8 hours, compared with 55 °C for 6 hours for PolyLite PLA.
Which should you choose?
Choose PLA if…
- The part must hold its shape and dimensions under load.
- Fine detail and fast printing matter, as with models and prototypes.
- Your printer has a long or loose filament path that struggles with flexible filament.
- The part does not need to absorb impacts.
Choose TPU / flexible filament if…
- The part must bend, stretch or seal, such as a gasket, grip or bumper.
- Abrasion and repeated impact matter more than stiffness.
- You can print slowly and adjust the extruder for flexible filament.
- You can pick a Shore hardness to match the part, since Prusa notes TPU ranges widely.
Common questions
Can TPU print on a PLA printer?
Often, with changes. Prusa recommends slow speeds, low retraction and a loosened extruder idler, and notes some machines need a bypass for the filament path. Softer grades are harder to feed.
What does Shore 95A mean?
It is a hardness rating for elastomers. Polymaker lists PolyFlex TPU95 at 95A, and Prusa says TPU filaments typically range from about 60A to 90A; lower numbers are softer and harder to print.
Does TPU need drying?
Prusa says flexible filaments are hygroscopic and much harder to print when wet. Polymaker recommends 70 °C for 8 hours for PolyFlex TPU95.
Sources
- PolyLite PLA technical data sheet Polymaker · Checked 2026-11-02
- PolyFlex TPU95 technical data sheet Polymaker · Checked 2026-11-02
- PLA Prusa Research · Checked 2026-10-15
- Flexible materials Prusa Research · Checked 2026-10-15
- Drying filament Prusa Research · Checked 2026-10-15
This comparison summarizes the cited documentation; it is not a lab test. Properties vary by brand, grade, print settings and orientation, so check the data sheet for the exact product you buy.