This is the one comparison on the site where the two sides are not the same kind of thing. TPU — thermoplastic polyurethane — is a defined chemistry, and a profile that works on one brand's TPU will get you most of the way with another's. TPE is an umbrella term covering styrenic, olefinic and several other elastomer families, and two spools both labelled TPE can behave like different materials entirely.
For almost everyone, that asymmetry settles it: buy TPU, and buy TPE only when you have a specific reason and a specific brand you have tested.
How wide "TPE" actually is
The stored figures make the point without argument. TPU 95A's density sits between 1.15 and 1.24 g/cm³ — a normal spread for a filament. TPE's runs from 0.9 to 1.2, and that range is genuine rather than cautious, because the label covers chemistries with different backbones.
Follow it through to something practical. A kilogram of 1.75 mm filament at the light end of that range is 461.95 m; at the heavy end, 346.46 m. That is 115.49 m of difference — a 25% reduction in length for a 33.333% increase in density — on two spools that carry the same three letters. The point is not that TPE is light. It is that "TPE" does not name a density at all, so any length per kilogram derived from the label is a guess — weighing the spool and working backwards through the length and weight converter is the only route to a figure you can rely on here.
You cannot estimate how much of a TPE spool a job will use without knowing which TPE it is. That is not a criticism of the material; it is a description of what the category means.
The stored tensile figures say the same thing more sharply: TPE spans 8 to 30 MPa. The bottom of that range is a material that tears in your hands and the top is comparable to TPU. Both are correctly labelled.
What that means for a profile
TPU 95A carries a difficulty rating of 3 on this site; TPE carries 5, and the reason is not that TPE is harder to print in some absolute sense. It is that nothing you learn transfers.
- Nozzle temperature: TPU 95A wants 220–245 °C, TPE 210–240 °C, and where inside that band a given TPE wants to sit depends on which chemistry it is.
- Shrinkage: 0.5 to 1.5% for TPU 95A against 0.8 to 2.5% for TPE, and the stored note is explicit that TPE varies more between grades than whole material families vary elsewhere on this site.
- Drying: both need it, but the correct schedule depends on the base chemistry, which the label rarely states.
With TPU you tune once and reuse. With TPE you tune per product line and start again when the brand reformulates or you switch supplier. If you print flexibles occasionally, that overhead is the whole cost of the decision.
Where TPE is genuinely the right buy
It is not a bad material and there are real reasons to reach for it.
Very soft parts. The softest usable TPU grades stop around the low 80s on the Shore A scale. Styrenic TPEs go softer, into territory that feels like rubber rather than firm plastic, which matters for overmoulded grips, wearables and prosthetic liners.
Overmoulding onto a rigid part. Some TPE grades bond well to polypropylene and to other olefins in a way TPU does not, which is why the injection-moulding world uses them for two-shot soft-touch surfaces.
Cost, occasionally. TPE ranges from $30 to $70 per kilogram against TPU 95A's $25 to $45, so it is generally the dearer option — but the very softest grades of each are closer, and a specific TPE can undercut a specialist soft TPU.
A brand you have already proven. The variability argument disappears entirely once you have a spool you know. If you have tested a particular TPE and it works, the category's reputation is irrelevant to you.
Where TPU wins without much argument
Everything where predictability is worth more than the last few points of softness: printer feet, phone cases, gaskets, seals, RC tyres, cable strain reliefs, drive belts.
TPU also has the better documentation ecosystem. Community profiles, published settings and troubleshooting advice overwhelmingly assume TPU, so when something goes wrong you are searching a much larger body of directly applicable experience.
And if the softness is the point, TPU offers it as a graded ladder rather than a lottery — TPU 95A against 85A covers what changes as you go down it, and the answer is mostly "how carefully your extruder has to feed".
Buying either one sensibly
- Check the Shore hardness, not the name. It is the only specification on the label that predicts how the part will feel.
- Prefer a brand that publishes a technical data sheet. For TPE this is close to essential, because the data sheet is the only place the chemistry is named.
- Buy a small spool first. Flexible filaments are the category where a sample spool most reliably saves money.
- Weigh what arrives. If you are estimating jobs from length, a TPE spool's density is worth confirming rather than assuming — the numbers above show how far the assumption can be out.
The honest summary: TPU is a material you can plan around. TPE is a shopping category, and it can be an excellent one once you have narrowed it down to a single product you trust.