Best TPU Filaments for Flexible Prints in 2025

TPU (Thermoplastic Polyurethane) filament opens up a whole world of flexible 3D printing — phone cases, gaskets, shoe insoles, drone bumpers, watch bands, and more. However, printing flexible filaments is significantly harder than PLA or PETG, and filament quality makes an enormous difference in success rate.

The key metric for TPU is Shore hardness — measured on the A scale. Lower numbers mean softer/more flexible (85A is very soft), higher numbers are stiffer (98A approaches semi-rigid). Most general-purpose TPU is 95A, which offers a good balance.

1. NinjaTek NinjaFlex — Best Ultra-Flexible TPU

NinjaFlex is the filament that started the flexible printing revolution. At 85A Shore hardness, it's one of the softest TPU filaments available — prints feel genuinely rubbery and can stretch up to 660% before breaking.

This extreme flexibility comes at a cost: NinjaFlex is the hardest TPU to print on this list. It absolutely requires a direct-drive extruder (Bowden tubes are nearly impossible), slow print speeds (15-25mm/s), and careful retraction settings. But when you nail the settings, the results are incredible — smooth, flexible parts that feel professional.

The filament costs $42-50 per 0.5kg spool (note: half the standard weight), making it the most expensive option by far. But for applications requiring maximum flexibility — like custom phone cases, flexible hinges, or wearable items — nothing else comes close.

Best for: Experienced users who need maximum flexibility for phone cases, gaskets, seals, wearables, and highly elastic parts.

2. SainSmart TPU — Best Value TPU

SainSmart's 95A TPU is the sweet spot of flexibility, printability, and value. At $24-30 per kilogram, it's roughly a quarter the per-gram cost of NinjaFlex while still delivering good flexible prints.

The 95A hardness means parts are flexible but not floppy — they bounce back from compression and flex without feeling mushy. This is the ideal hardness for most practical applications like phone cases, bumpers, and vibration dampeners.

SainSmart TPU prints more easily than softer options. With a direct-drive extruder at 25-35mm/s, results are surprisingly consistent. Some users even report success with Bowden setups at very slow speeds with minimal retraction. The ±0.03mm tolerance is impressive for TPU.

Best for: Budget-conscious makers who need flexible parts for functional applications. Great first TPU for beginners.

3. NinjaTek Cheetah — Easiest TPU to Print

NinjaTek Cheetah is designed specifically to solve the printability problem of flexible filaments. It's a 95A TPU that's been formulated for faster printing speeds — up to 60mm/s, which is unheard of for flexible filaments.

The secret is Cheetah's slightly stiffer formulation that maintains 95A flexibility while resisting the buckling and jamming that plague softer TPUs. It feeds reliably through direct-drive extruders and even works with well-tuned Bowden systems.

At $38-46 per 0.5kg spool, it's not cheap — but the time saved from faster printing and fewer failed prints makes it worthwhile. Layer adhesion is excellent, and the surface finish is among the best of any TPU we've tested.

Best for: Users who want flexible prints without the extremely slow speeds and finicky settings of standard TPU.

4. Overture TPU — Best Budget Choice

Overture enters the TPU market with their characteristic value proposition — decent quality at an aggressive price. At $22-28 per kilogram, it's the cheapest TPU that still delivers usable results.

The 95A hardness is standard and the ±0.03mm tolerance is good. Prints are flexible and durable, though we noticed slightly more inconsistency compared to SainSmart or NinjaTek. Some sections of the spool had minor diameter variations that affected flow rate.

For learning TPU printing or making parts where cosmetic perfection isn't critical, Overture TPU is a solid choice. Like other Overture products, it ships with a build surface sheet and printing guidelines.

Best for: Budget experimenters who want to try TPU printing without a significant investment.

5. Polymaker PolyFlex TPU95 — Best Surface Finish

Polymaker's PolyFlex TPU95 brings their signature quality to flexible printing. The filament produces parts with an exceptionally smooth, matte surface finish that looks and feels premium. Layer lines are less visible than with most TPU filaments.

The ±0.03mm tolerance is consistent, and the filament feeds well through direct-drive extruders. Polymaker recommends print temperatures of 210-230°C — slightly lower than competitors, which helps reduce stringing. The lower temp also means less heat creep in the hot end.

PolyFlex comes in Polymaker's standard resealable packaging, and the color range includes some beautiful translucent options. Abrasion resistance is excellent — printed parts hold up well to repeated flexing and wear.

Best for: Users who need flexible parts that look great — watch bands, wearables, display items with flexible elements.

Buying Guide: How to Print TPU Successfully

Direct Drive vs Bowden

Direct-drive extruders are strongly recommended for TPU printing. The short filament path minimizes the flex and buckling that cause jams. If you only have a Bowden setup, use 95A or harder TPU, print very slowly (15-20mm/s), and disable or minimize retraction.

Speed Settings

Slow down significantly from your PLA/PETG speeds:

• 85A TPU: 15-25mm/s
• 95A TPU: 25-40mm/s (up to 60mm/s with NinjaTek Cheetah)
• Travel speed: Reduce to 100-150mm/s
• First layer: 15-20mm/s regardless of hardness

Retraction Settings

Retraction is tricky with TPU. Too much retraction causes jams; too little causes stringing.

• Direct drive: 0.5-2mm retraction, 25mm/s speed
• Bowden: 3-5mm retraction, 25mm/s speed (or disable entirely)
• Some users get best results with retraction disabled and "combing" enabled

Cooling

TPU benefits from moderate cooling — 50-70% fan speed. This helps with overhangs and stringing without sacrificing layer adhesion. Too much cooling can cause delamination.

Bed Adhesion

TPU adheres well to most surfaces. A heated bed at 50-60°C works well. Blue painter's tape also provides excellent adhesion. Avoid using adhesion aids — TPU can stick too well and be difficult to remove.

For an easier printing experience, start with Best PLA Filaments for Beginners. Need strong rigid parts instead? Check Best PETG Filaments for Strength and Durability. And keep your TPU dry with proper Filament Dryers and Storage Solutions.