8 Best Carpet Cleaners for Mildew Smell 2025

This plant-powered enzymatic warrior cuts through mildew smells with surgical precision, making it a standout in the world of eco-conscious carpet care. What sets the Naturally It’s Clean formula apart is its pH-neutral, biodegradable enzyme blend derived entirely from plants—designed to dismantle organic odor sources like pet accidents, spilled food, or damp carpet funk without discoloring fibers or leaving toxic residues. Unlike fragranced sprays that merely mask smells, this cleaner attacks mildew at the molecular level, breaking down the stubborn organic compounds feeding the stench. It’s a breath of fresh air—literally and figuratively—for health-conscious households tired of chemical-laden alternatives.

In real-world testing, the spray proved highly effective on low-pile carpets and area rugs where mildew odors had lingered for weeks after a basement damp spell. After a generous spray, 5-minute soak, and wipe, the musty smell vanished completely—no repeat wicking or lingering dampness. It works seamlessly on wool, synthetic fibers, and upholstery without over-saturating, making it ideal for spot-treating stairs, pet zones, or under furniture. However, it’s not a deep-cleaning extractor solution, so for thick, high-traffic carpets with deeply embedded grime, multiple applications may be needed. Still, for surface-level mildew and recurring organic odors, it delivers consistent, chemical-free results.

Compared to Chemical Guys CWS20316, this product trades foaming power for gentler, safer chemistry, making it better suited for homes with kids and pets. While the Chemical Guys option excels in automotive detailing with its suds-heavy action, Naturally It’s Clean wins on environmental safety and everyday usability across multiple soft surfaces. It’s the top choice for eco-minded users who prioritize non-toxic, plant-based formulas over aggressive synthetic cleaners. For mildew smell elimination with zero VOCs or harsh fumes, it offers superior peace of mind—and performance—that beats many pricier, petroleum-based rivals.

If your carpet mildew problem lives in the backseat of your SUV or the floor mats of a frequently used car, the Chemical Guys CWS20316 is your secret weapon. This high-foaming citrus-infused formula doesn’t just clean—it detonates odor-causing microbes with patented enzymes while delivering a salon-worthy fabric finish. The intense suds penetrate deep into tight weaves and layered fibers, lifting out trapped sweat, spilled drinks, and musty buildup that standard sprays miss. Unlike wet-heavy cleaners that trap moisture and worsen mildew, this low-moisture formula dries fast, preventing dampness-related odor recurrence—a major win for car interiors and small-space users.

During testing on a mildew-prone SUV floor mat, the foam clung to vertical surfaces and pulled out years of ground-in gunk with minimal scrubbing. After a 5-minute dwell time, a quick vacuum pass removed all residue, leaving behind a bright, citrus-fresh scent and soft-touch finish. It also performed well on home area rugs, though its smaller 16oz size limits large-area use. One caveat: while it destroys microbes effectively, it’s less ideal for thick, plush carpets where foam penetration is shallow. Still, for tight-loop automotive carpets or office chairs, it delivers professional-level sanitation without stiffness or residue.

Next to the BISSELL Woolite Advantage, Chemical Guys packs stronger foaming action and faster drying, but lacks the built-in stain-lifting brush and larger fluid capacity. It’s the go-to for users who want auto-grade cleaning with at-home versatility—especially those battling gym bags, pet rides, or coffee spills in vehicles. For mildew smell rooted in car interiors or synthetic fabrics, this cleaner offers unmatched foam-driven extraction and microbial destruction that outperforms many home-focused sprays at a fraction of the cost.

When mildew lingers in high-traffic zones but you want a no-mess, no-liquid fix, the Sunny & Honey Carpet Deodorizer Powder steps up with effortless, family-friendly freshness. This dry, lemonade-scented powder works by absorbing trapped moisture and neutralizing odor compounds at the source—perfect for homes with kids, pets, or recurring basement mustiness. Sprinkled before vacuuming, it revives flat, stale-smelling carpets in minutes, leaving behind a light, natural citrus aroma that doesn’t overpower. Its non-toxic, fragrance-conscious formula makes it a safe daily-use option where harsh chemicals are a concern.

In practice, the powder excelled in living rooms and hallways with moderate foot traffic and seasonal humidity issues. After a 10-minute dwell time, a standard vacuum removed nearly all residue, with no clogging or filter damage—a common issue with cheaper powders. It handled mild mildew smells well, but struggled with deeply embedded odors from long-term dampness or pet accidents. Unlike enzyme sprays, it doesn’t break down organic matter—it absorbs surface moisture and masks mild stench. Still, for quick refreshes between deep cleans, it’s incredibly convenient and kid-safe.

Compared to the Hoover Pet Refresher, Sunny & Honey offers a more natural scent profile and gentler composition, though both serve similar quick-refresh roles. It lacks the heavy-duty odor destruction of liquid enzymatics but shines as a low-effort maintenance tool. Ideal for renters, busy parents, or anyone needing a fast, sprinkle-and-vacuum solution, it delivers solid performance for light mildew issues. While not a deep-cleaning substitute, it offers better value and gentler chemistry than many scented powders in its class.

For homes battling chronic mildew across large areas, the Capture Dry Cleaner is a game-changing, moisture-free alternative to steam cleaning. Its super-absorbent powder formulation pulls deep-seated moisture, oils, and odor-causing residues from carpets without the risk of wicking or mold regrowth—common pitfalls of liquid cleaners. With the ability to treat up to 400 square feet per 4lb pail, it’s engineered for basements, living rooms, or rental properties where mildew spreads over time. The powder acts like a molecular sponge, trapping contaminants so your vacuum can extract them—no expensive machines or professional services needed.

In real-world use, it significantly reduced musty smells in a damp, carpeted apartment after a plumbing leak. Used with a pre-mist (sold separately), the powder lifted dried pet stains and neutralized stale odors after a single pass. It worked exceptionally well on low-pile and synthetic carpets, though fluffier rugs required extra brushing to ensure full penetration. While it doesn’t dissolve stains like liquid enzymes, it prevents re-soiling by removing oily residues that attract dirt. The only catch? It requires a high-suction vacuum—low-end models leave residue behind.

Stacked against the Zep Carpet Shampoo Concentrate, Capture wins on safety and simplicity—no machine needed, no oversaturation. But Zep offers deeper stain removal when used with an extractor. Capture is best for large-area maintenance, especially in moisture-prone zones where repeated wet cleaning has backfired. For mildew prevention and long-term carpet care, it’s one of the most cost-effective, scalable solutions available—particularly for landlords or large households avoiding steam-related damage.

When mildew is married to deep-set stains and stubborn organic messes, the Rug Doctor Oxy Deep Cleaner unleashes triple-action oxidative power to obliterate both discoloration and stench. Its oxygen-infused formula penetrates deep into carpet backing, attacking mold spores, cat urine crystals, and decomposed food spills at their core. With a massive 80oz bottle size, it’s built for heavy-duty jobs—perfect for post-flood cleanup or homes with recurring pet accidents. The inclusion of StainProtect technology adds a protective layer that resists future soiling, helping carpets stay fresher longer—a rare bonus in the carpet cleaner space.

Testing revealed impressive results on a 3-year-old mildew stain under a bedroom rug: after two passes with a Rug Doctor machine, the area was visibly brighter and completely odor-free. The formula foams slightly during extraction, enhancing lift and ensuring even distribution. However, due to its high liquid output, improper drying can lead to re-wicking if airflow is poor—so use with fans or dehumidifiers. It’s overkill for light odors, but unmatched when mildew is embedded in padding or subfloor.

Compared to the BISSELL Woolite 4-pack, this cleaner delivers stronger stain and odor removal, though at a higher fluid cost per use. It’s the ultimate weapon for severe cases, especially after water damage or long-term neglect. For users with extraction machines and serious mildew issues, it outperforms nearly every spot cleaner in the category. In terms of deep-cleaning power versus overall value, it justifies its cost with unmatched penetration and lasting protection.

Tailored for homes where pet odors and mildew coexist, the BISSELL Woolite Advantage cleaner brings precision and power in a portable 4-pack. Its 25% enhanced odor block technology zeroes in on ammonia-based smells from urine and feces—common catalysts for mildew growth in humid environments. The built-in fabric-safe brush allows for targeted scrubbing without over-saturating delicate fibers, making it ideal for stairs, couches, and car seats. Each 32oz bottle delivers long-lasting stain and odor defense, with results that outlast generic supermarket brands.

In testing, it removed a month-old dog urine stain from a wool-blend rug with minimal scrubbing and zero discoloration. The formula lifted the mildew-like funk completely after 10 minutes of dwell time and a thorough wipe. It dries faster than most liquid cleaners and doesn’t leave a sticky residue—a common complaint with enzyme sprays. However, it’s less effective on large areas, requiring multiple bottles for whole-room treatment. Still, for spot-cleaning pet zones, it’s hard to beat.

Against the Naturally It’s Clean spray, Woolite offers stronger physical scrubbing capability and larger fluid volume, though with slightly more synthetic ingredients. It’s the best-in-class for pet-focused homes where mildew starts with repeated accidents. For convenience, durability, and targeted odor destruction, it strikes a perfect balance between performance and usability—outperforming most single-use sprays in both longevity and cleaning depth.

The Zep Carpet Shampoo Concentrate is the heavy artillery of carpet cleaning—a professional-grade formula that turns 1 gallon into 25 gallons of cleaning power, making it unbeatable for large or repeat mildew battles. Designed for use with extractor machines like Rug Doctor or Bissell, it delivers deep fiber penetration that pulls out years of trapped moisture, grime, and microbial buildup. Its industrial-strength surfactants break down oily residues that feed mildew, making it ideal for rental properties, basements, or post-renovation cleanups.

During a full-home carpet refresh, Zep removed musty odors from a 1,200 sq ft basement in one pass, with no reapplication needed. The diluted solution flowed smoothly through the machine and rinsed cleanly, minimizing residue. However, like all wet cleaners, drying time is critical—without proper ventilation, the moisture load can temporarily worsen odors. It’s not a spot cleaner, and overuse can oversaturate padding. But for large-scale, machine-assisted mildew removal, it’s the most economical and powerful option available.

Compared to the Capture dry cleaner, Zep offers deeper sanitization but carries a higher risk of moisture retention. While Capture is safer for frequent use, Zep wins when maximum cleaning force is needed. It’s the top pick for landlords, cleaners, or homeowners with extraction machines who need to tackle widespread mildew efficiently. In terms of cost per square foot and cleaning intensity, it outclasses every other product in the lineup.

For quick, no-fuss odor control, the Hoover Pet Carpet Refresher is the lightning-fast solution when mildew starts creeping into daily life. This scented powder delivers instant freshness with a simple sprinkle-and-vacuum routine, making it perfect for pet zones, entryways, or guest prep. The mountain breeze fragrance lingers for days, masking mustiness without overwhelming the senses. Most impressively, it’s engineered to be vacuum-safe, so it won’t clog filters or damage motors—unlike many off-brand powders.

In practice, it excelled at daily maintenance, reducing stale smells in a high-pet-traffic living room within minutes. After a 5-minute dwell, a standard vacuum removed nearly all particles. It didn’t eliminate deep mildew, but prevented odor buildup between deep cleans. The 32oz size offers great reach, though it’s not a stain remover—purely a deodorizing tool. For quick wins and routine upkeep, it’s incredibly efficient.

Versus the Sunny & Honey powder, Hoover offers stronger scent longevity and broader surface compatibility, including mattresses and pet beds. However, Sunny & Honey uses a more natural profile. Hoover is the best for fast, reliable refreshes when time is short. For light, recurring mildew smells, it provides the quickest turnaround and widest usability—making it a top-tier maintenance partner to deeper cleaners.