After writing about how dog pee nearly destroyed my life in San Francisco Download, I thought I was done – if not done journalistically (kidding, of course), at the very least talking about pet stains. But when the opportunity came up to test enzyme cleaners for Reviewed World, I jumped at the chance.
After all, I knew the pain so well: I’d seen firsthand how the wrong cleaner can turn a minor problem into a household crisis that tests the strength of your marriage.
For those unfamiliar with my previous work in pet urine, Mochi, my family’s mischievous rescue pup, had tested every ounce of patience we had during his potty-training phase. No matter how many so-called “pet stain removers” I tried, he kept marking the same spot in our living room—until I found Earthworm Pet Stain & Odor Eliminator, which finally broke the cycle and brought some sanity to our household. You can read that saga in the SFD.
That experience led me down a rabbit hole of enzyme cleaning products, and now, I’m thrilled to be putting three of the leading enzyme-based pet cleaning products to the test: Earthworm, Nature’s Miracle, and Bissell.
First: What is an Enzyme-Based Pet Cleaner?
Most cleaning sprays work by masking odors or using harsh chemicals to dissolve stains on the surface. The problem? That approach doesn’t eliminate the underlying scent markers that pets use to identify “their spot.” Even if the stain looks clean to the human eye (and smells fresh to us), your pet’s powerful nose can still pick up microscopic traces of urine, signaling to them that this is still a designated bathroom area. That’s why dogs and cats often return to the same spot, even after repeated cleanings.
Enzyme cleaners work at the molecular level to tackle this problem differently. Instead of just covering up odors with fragrances or chemically breaking down visible stains, enzymatic cleaners use specialized proteins that accelerate natural biochemical reactions to break down organic waste completely.
Urine contains urea, uric acid, creatinine, and ammonia, among other compounds. While traditional cleaners can break down some of the surface-level elements, uric acid crystals are particularly stubborn. These crystals embed into carpet fibers, wood flooring, or upholstery and can remain even after repeated cleanings—continuing to release odors and acting as a beacon for pets.
Enzyme-based cleaners target these crystals directly. The enzymes in the cleaner act as biological catalysts, triggering a process that digests and deconstructs urine molecules into harmless byproducts like carbon dioxide and water. As a result, there’s no residue left behind—nothing for your pet to smell, nothing for them to return to, and nothing left to attract bacteria or re-trigger the ammonia-like scent that happens when dried urine rehydrates in humidity.
Evaluating the Three Most Popular Enzyme-Based Pet Stain Cleaning Products
I tested all three of these cleaners under the same conditions—on pet urine spots, with the same amount of dry time, and the same cleaning method (spray, let sit, blot). Here’s how they stacked up.
Bissell Pet Stain & Odor Remover: Is There Anything in This Bottle?
Let’s start with the one that felt the most like a scam. Bissell Pet Stain & Odor Remover promises to eliminate pet odors, but after testing, I’m not even sure it contains any actual cleaning ingredients.
I sprayed it on a fresh stain, waited the recommended five minutes, and blotted. The stain looked slightly lighter, but the odor? Still there. The next morning, the smell was just as strong, and my dog went right back to the same spot. A second round of cleaning didn’t help. It felt like I was just spraying water on the stain.
Online reviews back this up—tons of users report it just doesn’t work. If there are enzymes in here, they’re either in such small amounts they don’t do anything, or they’re being rendered ineffective by the rest of the formula. Either way, this was a hard pass.
Nature’s Miracle: Effective, But Left Me With Questions
This is one of the most well-known pet cleaners on the market, and I can confirm that it does work—sort of. It removed both fresh and set-in stains and made the area smell better.
But here’s the issue: the scent is overpowering. According to what I found on Reddit and in reviews, it seems like this is a new problem based on a formula change in 2024.
But if Nature’s Miracle is an enzyme-based cleaner, why does it smell like a department store cleaning aisle? A strong artificial fragrance isn’t what I want in a natural cleaner. Worse, the scent lingered for hours. And I don’t even have much of a nose – so if you have a sensitive snout, stay away from Nature’s Miracle at all costs.
The goal of a good cleaner is to eliminate odors, not drown them in perfume. It works, but it’s not my pick for an environmentally friendly or pet-safe solution.
The Clear Winner: Earthworm Pet Stain & Odor Eliminator
From the moment I first tested this, it felt like a completely different class of cleaner. No harsh chemicals. No artificial scent bomb. Just a mild, natural citrus smell that disappears as it dries. But most importantly? It works.
Earthworm’s Pet Stain and Odor Eliminator formula is 100% enzyme-based, and you can tell.
Within minutes of applying it, urine odors completely disappeared. It worked equally well on fresh stains and older spots that had dried. Best of all, I know from months of testing that it has prevented my dog from returning to the same area—proving that it actually eliminated the scent markers at a biological level.
The ingredient list is refreshingly simple and non-toxic. It’s biodegradable, plant-based, and free of synthetic dyes or fragrances. For pet owners who care about sustainability (or just don’t want a bunch of chemicals in their home), this is hands-down the best choice.
And it doesn’t hurt that Earthworm is a family-owned, woman-operated business. It’s nice to vote with your dollars on things like that.
Which Enzyme-Cleaner is Best for Pet Stains?
If you want an enzyme cleaner that actually does its job, skip the cheap stuff and go straight to Earthworm Pet Stain & Odor Eliminator.
Bissell? Might as well be spraying water. Nature’s Miracle? Effective, but the overpowering scent and questionable formula don’t make it my top pick.
Earthworm delivers on every front: 100% enzyme-based, zero harsh chemicals, no strong fragrance, and actually prevents repeat accidents. For pet owners serious about keeping their home clean while using a safe, eco-friendly product, this is the best choice on the market.
Would I buy it again? I already have.
What do you think? Reach Kevin on Mastodon.
For more about our review methodology, click here.
