Comparison
Creality Space Pi Filament Dryer vs SUNLU FilaDryer S4: Which Is Better in 2026?
| At a glance | Creality Space Pi Filament Dryer | SUNLU FilaDryer S4 |
|---|---|---|
| Rating | ★★★★★ 4.3/5 | ★★★★⯨ 4.5/5 |
| Price | $40-60 | $60-80 |
| Best for | Beginners adding their first filament dryer on a budget. | Anyone printing PETG, TPU, or nylon, or in a humid climate. |
| Guarantee | Amazon return policy applies | Amazon return policy applies |
| Check Today's Price → | Check Today's Price → |
Wet filament is the print problem almost nobody diagnoses correctly. Prints start stringing, surfaces go rough, the nozzle pops and hisses mid-print — and people re-level the bed and swap nozzles for a month before anyone points at the roll of PETG that's been sitting in open air since spring. Both of these dryers fix that. The real difference between them is capacity: the Creality Space Pi holds one spool, the SUNLU FilaDryer S4 holds two, and nearly everything else in this decision flows from that.
Worth saying plainly: these are not rival designs. They're two sizes of the same idea — a heated box that pulls moisture out of filament and lets you feed straight from it while a print runs. The Space Pi sits at $40–60 with a 4.3 rating; the S4 at $60–80 with a 4.5. Twenty dollars and one extra spool bay separate them.
The picks
Creality Space Pi Filament Dryer
Compact, affordable single-spool dryer for keeping rolls print-ready.
$40-60 · Amazon return policy applies
The Space Pi is the starter move. One spool, small footprint, simple controls: drop a roll in, set it, print through it. If you mostly run PLA with occasional PETG and you've never dried filament before, this is the cheapest way to find out how many of your "mystery" failures were moisture all along. Its trade-offs are honest ones — a single bay, a limited max temperature that rules out serious nylon work, and controls that are genuinely basic. For a first dryer, none of that matters much.
SUNLU FilaDryer S4
Large dual-capacity dryer that fixes the #1 cause of failed prints: wet filament.
$60-80 · Amazon return policy applies
The S4 is the same idea, scaled up. Two spools at once, print-from-the-box feeding, and big readable controls you can check across the room. Dual capacity is more useful than it sounds: dry the next roll while printing from the current one, or keep both feeds dry on a multi-material job. The costs are real too — it eats bench space, the fan is audible, and a truly soaked roll takes its time.
How to actually choose
Decide by material first, budget second. PLA is the most forgiving of the common filaments; it absorbs moisture slowly enough that casual printers can get away with sloppy storage for a while. PETG, TPU, and nylon are the opposite — they pull water out of the air fast, sometimes within days of opening the bag, and that's exactly the crowd the S4 is built for. Humid climate? Same answer.
Then think about workflow. A single bay means the dryer is always occupied by whatever you're printing — drying the next roll means waiting. Two bays turn that into a pipeline.
One more thing: a dryer isn't storage. It fixes wet filament; sealed containers with desiccant keep it fixed. The cheap, complete system is one of these boxes plus a few airtight bins of silica for the spools you're not using.
Who should skip both
If your prints fail at the first layer, that's bed leveling or adhesion, not moisture — no dryer fixes it. If you print only PLA, live somewhere dry, and go through spools within a few weeks of opening them, you can genuinely wait. And if nylon is your daily material, check the temperature ceiling on anything in this price class before depending on it — the Space Pi's limited max temp makes it the wrong tool for that job.
Bottom line
These two are near-identical at the core, so buy by capacity. One printer, mostly PLA, first dryer ever: get the Space Pi and pocket the twenty bucks. Regular PETG or TPU, humid air, more than one roll in rotation: the S4's second bay pays for itself in prints that don't fail. The only wrong answer is printing hygroscopic filament and drying nothing.