🏆 Quick Answer
Best Overall Filament Dryer: SUNLU FilaDryer S2 — Reliable, affordable, and fits standard 1kg spools with accurate temperature control up to 70°C. For serious storage, the Polymaker PolyBox Edition II combines drying and long-term storage in one unit.
Moisture is the silent killer of 3D prints. When filament absorbs water from the air, you get bubbling, stringing, poor layer adhesion, and that annoying popping sound during extrusion. Hygroscopic filaments like Nylon, PETG, TPU, and even PLA are all vulnerable — and the longer they sit out, the worse the problem gets.
A dedicated filament dryer or proper storage solution is one of the best investments you can make for consistent print quality. We've tested and compared the top options to help you choose the right one for your setup.
| Product | Max Temp | Capacity | Drying Time | Price Range | Rating | Link |
|---|---|---|---|---|---|---|
| SUNLU FilaDryer S2 | 70°C | 1 spool | 6-12 hrs | $45-55 | ⭐ 4.7/5 | Check Price |
| SUNLU FilaDryer S4 | 70°C | 4 spools | 6-12 hrs | $120-140 | ⭐ 4.6/5 | Check Price |
| Polymaker PolyBox Edition II | 70°C | 1 spool | 8-12 hrs | $55-65 | ⭐ 4.7/5 | Check Price |
| eSUN eBOX Lite | 55°C | 1 spool | 8-16 hrs | $35-45 | ⭐ 4.4/5 | Check Price |
| PrintDry Pro | 65°C | 2 spools | 6-12 hrs | $90-110 | ⭐ 4.5/5 | Check Price |
| Cereal Container + Desiccant (DIY) | N/A | 1 spool | N/A | $10-15 | ⭐ 4.2/5 | Check Price |
1. SUNLU FilaDryer S2 — Best Overall Filament Dryer
The SUNLU FilaDryer S2 is the most popular filament dryer on the market, and it earned that position by delivering reliable performance at a price that makes sense for hobbyists. At $45-55, it's an easy recommendation for anyone dealing with moisture issues.
The S2 features a 360° surround heating element that evenly dries your spool, with adjustable temperature from 35°C to 70°C — high enough to handle even Nylon and Polycarbonate. The built-in LCD displays the current temperature and remaining time, and you can set drying durations up to 24 hours.
It accommodates standard 1kg spools up to 210mm in diameter, and a filament feed hole in the side lets you print directly from the dryer. This "print while drying" feature is a game-changer for hygroscopic materials like TPU and Nylon that start absorbing moisture within hours of exposure.
✅ Pros
- Excellent temperature range (35-70°C)
- Print-while-drying filament feed hole
- Accurate temperature control
- Compact, clean design
- Very affordable for what it offers
❌ Cons
- Only fits one spool at a time
- No built-in humidity sensor
- Lid seal could be tighter on some units
Best for: Most 3D printing hobbyists who need a reliable, affordable dryer. Perfect for occasional drying and printing directly from the unit with moisture-sensitive filaments.
2. SUNLU FilaDryer S4 — Best Multi-Spool Dryer
If you run multiple printers or frequently switch between filaments, the SUNLU FilaDryer S4 is worth the upgrade. It holds up to four spools simultaneously, each with its own filament feed-through port so you can dry and print from all four at once.
The S4 uses the same proven heating system as the S2 but in a larger enclosure. Temperature range remains 35-70°C with a clear front panel that lets you monitor your spools. The internal fan circulates warm air evenly across all four spools, and SUNLU claims uniform drying within ±2°C across the chamber.
At $120-140, it costs less than buying four individual S2 units, making it the better value for multi-printer setups. The footprint is surprisingly reasonable — about the size of a large shoebox.
✅ Pros
- Dries 4 spools simultaneously
- Individual feed ports for each spool
- Even heat distribution with internal fan
- More cost-effective than multiple single dryers
- Clear front panel for monitoring
❌ Cons
- Takes up more desk space
- Higher upfront cost
- Heavier and harder to move around
Best for: Print farms, multi-printer setups, or anyone who works with several hygroscopic materials and wants to keep them all dry simultaneously.
3. Polymaker PolyBox Edition II — Best Dryer + Storage Combo
The Polymaker PolyBox Edition II takes a different approach — it's designed as both a dryer and a long-term storage solution. The sealed enclosure with integrated desiccant holder keeps filament dry indefinitely, while the built-in heating element can actively dry wet spools.
What sets the PolyBox apart is its attention to sealing. The lid uses a silicone gasket that creates a genuinely airtight seal, and a built-in humidity indicator shows you the moisture level inside at a glance. There are two PTFE tube feed-throughs with quick-connect fittings for clean, low-friction filament paths.
Temperature maxes out at 70°C, and while it doesn't have the same precise timer controls as the SUNLU S2, the combination of active drying and passive storage makes it the most versatile option on this list.
✅ Pros
- Excellent airtight seal for long-term storage
- Built-in humidity indicator
- PTFE tube feed-throughs with quick-connect
- Works as both dryer and storage box
- Quality build from a trusted brand
❌ Cons
- More expensive than basic dryers
- Limited timer controls
- Single spool capacity
Best for: Users who want a single solution for drying and storing filament. Ideal for those in humid climates where long-term moisture protection is critical.
4. eSUN eBOX Lite — Best Budget Dryer
The eSUN eBOX Lite is the most affordable dedicated filament dryer worth buying. At $35-45, it undercuts the competition while still delivering functional drying performance for common filaments like PLA, PETG, and TPU.
The eBOX Lite heats up to 55°C, which is sufficient for PLA and PETG but falls short for high-temperature materials like Nylon and Polycarbonate. It features a built-in filament weight scale on the bottom — a clever addition that lets you estimate remaining filament without removing the spool.
The design is simple: a translucent enclosure with a top-loading lid and a single filament exit hole. Temperature control is basic with preset options rather than exact degree settings. For the price, it does exactly what most hobbyists need.
✅ Pros
- Most affordable dedicated dryer
- Built-in filament weight scale
- Simple, easy-to-use interface
- Compact and lightweight
- Good enough for PLA and PETG
❌ Cons
- Max 55°C — not enough for Nylon/PC
- Basic temperature presets only
- Seal is not as tight as higher-end options
- Slower drying times
Best for: Budget-conscious hobbyists who mainly print with PLA and PETG and want a basic dryer without spending $50+.
5. PrintDry Pro — Best Dual-Spool Dryer
The PrintDry Pro splits the difference between single and four-spool dryers by offering a two-spool capacity. It's a solid choice for users who run two printers or want to dry multiple materials without the bulk of the S4.
The Pro version features improved heating elements over the original PrintDry, reaching 65°C with better heat distribution. Two independent feed-through holes let you print from both spools simultaneously. The stacking design means spools sit on top of each other, keeping the footprint small.
Build quality feels a step above the SUNLU units — the latching mechanism is more robust and the seal is tighter. At $90-110, it's priced fairly for what you get.
✅ Pros
- Two-spool capacity in a compact form
- Good build quality and tight seal
- Dual feed-through ports
- Stacking design saves desk space
- Solid temperature performance
❌ Cons
- 65°C max — slightly below ideal for Nylon
- More expensive per spool than the S4
- Less common — fewer reviews and community tips
Best for: Two-printer setups or users who want dual-spool drying without the bulk and cost of a four-spool unit.
6. DIY Cereal Container + Desiccant — Best Budget Storage
You don't always need to spend money to solve the moisture problem. A large airtight cereal container from any kitchen store, combined with rechargeable silica gel desiccant, is the classic budget storage solution that countless makers rely on.
Buy a container large enough to hold a standard spool (at least 8" diameter and 4" tall), drill a small hole for a PTFE tube feed-through, and toss in 100-200g of indicating silica gel beads. When the beads turn from orange to green (or blue to pink depending on type), pop them in the oven at 120°C for two hours to recharge.
This won't actively dry wet filament — you'll need a food dehydrator or dedicated dryer for that. But for keeping already-dry filament in good condition, it works remarkably well at a fraction of the cost.
✅ Pros
- Extremely cheap ($10-15 total)
- Customizable to any spool size
- Rechargeable desiccant is reusable indefinitely
- Easy to build multiples for large collections
❌ Cons
- Cannot actively dry wet filament
- Seal quality varies by container
- No temperature control
- Requires manual desiccant monitoring
Best for: Makers on a tight budget who want to protect their filament collection without investing in dedicated hardware. Great as a complement to a single dryer.
Buying Guide: How to Choose a Filament Dryer or Storage Solution
Active Drying vs. Passive Storage
Active dryers use heat to evaporate moisture that's already been absorbed into filament. Passive storage containers with desiccant prevent future moisture absorption but can't fix already-wet filament. Ideally, you want both — a dryer for recovery and storage containers for prevention.
Temperature Range
Different filaments require different drying temperatures. PLA dries well at 45-50°C, PETG at 55-65°C, and Nylon at 70-80°C. If you print with various materials, get a dryer that reaches at least 70°C. Lower-temp dryers are fine if you only print PLA and PETG.
Capacity
Consider how many spools you use regularly. If you switch filaments frequently or run multiple printers, a multi-spool dryer saves time. Single-spool dryers are fine for hobbyists who focus on one material at a time.
Print-While-Drying
The ability to feed filament from the dryer directly to your printer is incredibly useful for hygroscopic materials. Look for PTFE tube feed-through holes with smooth paths that won't add friction to your filament feed.
Seal Quality
The entire point of these products is moisture control, so the seal matters. Look for silicone gaskets, latching mechanisms, and designs where the lid doesn't need to be perfectly aligned to seal. Poor seals mean wasted energy and ineffective drying.
Humidity Monitoring
Some units include hygrometers or humidity indicators. These help you know when drying is complete and when stored filament needs attention. If your dryer doesn't include one, a $5 mini hygrometer from Amazon fits inside most enclosures.
Frequently Asked Questions
Common signs of wet filament include: popping or crackling sounds during extrusion, excessive stringing, bubbles or rough spots on print surfaces, poor layer adhesion, and a noticeable decline in print quality compared to when the spool was new. Nylon and TPU are especially susceptible and can absorb problematic amounts of moisture in just a few hours of open-air exposure.
Drying time depends on the material and how wet it is. Lightly damp PLA typically dries in 4-6 hours at 45°C. Severely wet PETG can take 12-18 hours at 60°C. Nylon may need 12-24 hours at 70°C. As a rule, longer is better — overdrying won't hurt the filament. Set your dryer overnight for best results.
Yes! A food dehydrator with adjustable temperature control works well for drying filament. Look for one with circular trays that you can remove to fit a spool. The main downsides are less precise temperature control and no filament feed-through for printing while drying. Many makers start with a $30-40 food dehydrator before upgrading to a dedicated unit.
Indicating silica gel never truly expires — it just needs recharging. When the beads change color (indicating they're saturated), spread them on a baking sheet and bake at 120°C (250°F) for 2-3 hours to drive out the moisture. They'll return to their original color and be ready to reuse. Most users recharge every 2-4 weeks depending on ambient humidity.
PLA is less hygroscopic than materials like Nylon or TPU, but it still absorbs moisture over time — especially in humid environments. If you use spools within a week or two and store them sealed, you may not need a dryer. But if you notice declining print quality on older spools, a dryer will fix the issue. At minimum, store PLA in airtight containers with desiccant.
Proper filament storage goes hand-in-hand with using quality materials. Check out our guide on Best PLA Filaments for Beginners if you're just getting started, or see our Best PETG Filaments for Strength and Durability for materials that especially benefit from dry storage. For more accessories to complete your setup, see our Best 3D Printing Tools and Accessories Kit guide.