Best Non-Toxic Shampoo

How many shampoos are actually non-toxic?

We analyzed 826 of the most popular shampoos and only 31, around 4%, qualified as non-toxic.

When we say a shampoo is “non-toxic,” we mean it meets the Welpr Standard, our precautionary consumer standard. We assess products across two main categories:

1. Flagged Ingredient: ingredients identified as hazards by regulators or scientific bodies that meet our criteria for exclusion.
2. Transparency Issues: incomplete ingredient disclosure or potential manufacturing contaminants that haven’t been resolved through credible finished-product testing.

These are precautionary judgments, not proof either way. Not meeting the Standard does not mean a shampoo is proven harmful. It means we identified a flagged ingredient, an unresolved information gap, or both. Meeting it doesn't guarantee a shampoo is harmless for every person or every use.

Flagged ingredients in shampoo

73 of the 826 products listed at least one ingredient flagged by the Welpr Standard. The table below shows how often each appeared, which organization identified the concern, and why it was flagged.

Transparency issues in shampoo

792 of the 826 shampoos had at least one disclosure gap or potential-contaminant flag.

These are two different information gaps. An undisclosed blend prevents us from checking every ingredient against the Standard. A potential-contaminant flag means the ingredient list raises a question that only testing can answer, not that we detected the contaminant. A brand can clear this flag by providing credible finished-product testing that satisfies the Welpr Standard.

A shampoo can have several findings, including both flagged ingredients and transparency issues, so the counts overlap.

What is non-toxic shampoo?

Non-toxic shampoo is shampoo made without ingredients that regulators or scientific bodies have identified as hazards. “Non-toxic” has no legal definition for cosmetics, so its exact meaning depends on who’s using it. At Welpr, it means a shampoo that meets our criteria for ingredient hazards, ingredient disclosure, and potential contaminants.

A hazard is a substance’s ability to cause harm. Risk is the likelihood of that harm under real conditions of use, which depends on how much you’re exposed to, how often, and by what route, a distinction the EPA uses in human health risk assessment. A flagged ingredient is a hazard, not a measured risk.

So does it matter for something you rinse off? A single wash is a brief exposure, far shorter than a lotion left on all day. But most people shampoo several times a week for decades, and FDA labeling rules don’t require brands to disclose how much of each ingredient is in the bottle. For many ingredients, the science can’t yet say how much reaches your body from shampoo. When the evidence and the label can’t settle the question, Welpr leans toward precaution: we favor shampoos that avoid flagged ingredients, disclose their full formula, and back up any contaminant questions with testing.

What’s in the bottle shapes which ingredients get flagged. Water is usually the first ingredient on a shampoo label, and water-based products need preservatives to keep bacteria and mold from growing once the bottle is opened. That’s why several of the ingredients we flag in shampoo are preservatives, including formaldehyde releasers like DMDM hydantoin and parabens like butylparaben.

Non-toxic vs. clean vs. natural vs. organic shampoo

“Non-toxic,” “clean,” “natural,” and “organic” are often used interchangeably on shampoo labels, but they describe different things.

Neither natural ingredients nor organic certification guarantees that a shampoo won’t cause irritation or an allergic reaction, because, as the FDA notes, an ingredient’s origin alone doesn’t determine its safety. That’s why a shampoo marketed as natural can still fail the Welpr Standard, and a shampoo containing synthetic ingredients can meet it.

Best non-toxic and clean shampoo

Retailers and brands each define “clean” with their own lists of excluded ingredients, such as Clean at Sephora, the Clean Ingredients badge in Ulta’s Conscious Beauty program, and Credo’s Clean Standard. These lists overlap but don’t match, so the same shampoo can qualify as clean under one and not another. Welpr applies one published Standard to every shampoo, including checks for undisclosed blends and potential contaminants.

Best natural shampoo

In shampoo, a “natural” claim usually points to cleansers derived from plant oils like coconut, or to scent from essential oils. Plant-derived cleansers are still made through chemical processing, and essential oils can contain the same fragrance allergens that synthetic fragrances do.

Best organic shampoo

The organic percentage on a shampoo doesn’t describe most of what’s in the bottle. Water is usually a shampoo’s main ingredient, and USDA rules leave water out when calculating a product’s organic percentage, so the number only covers the rest of the formula.

A shampoo containing organic ingredients also isn’t necessarily certified organic, because USDA organic certification has to cover the finished product. In the US, you’ll usually see one of two certifications on shampoo. USDA certification lets a shampoo be labeled “organic” when at least 95% of its ingredients are certified organic. NSF/ANSI 305 allows the label “contains organic ingredients” at 70% or more, and it permits some of the chemical processing that shampoo cleansers need to lather.

Common ingredients to avoid in shampoo

When reading the ingredient label on shampoo, here are some of the ingredients to be aware of:

Flagged ingredients regulators have identified as hazards

Zinc Pyrithione

Zinc pyrithione is used as an active ingredient in anti-dandruff shampoos. The European Commission flags it for reproductive toxicity, and it is prohibited in cosmetics in the EU.

DMDM Hydantoin

DMDM hydantoin is a preservative that helps prevent microbial growth in shampoo. The Washington State Department of Ecology flags it as a formaldehyde releaser, which Washington restricts when intentionally added to cosmetics.

Diazolidinyl Urea

Diazolidinyl urea helps preserve shampoo by preventing microbial growth. The Washington State Department of Ecology flags it as a formaldehyde releaser, which Washington restricts when intentionally added to cosmetics.

Isoeugenol

Isoeugenol is a fragrance ingredient used to add scent to shampoo. The World Health Organization’s International Agency for Research on Cancer (IARC) classifies it as possibly carcinogenic to humans.

Pentasodium Pentetate

Pentasodium pentetate binds metal ions, helping keep shampoo formulas stable. The European Commission flags it for reproductive toxicity, and it is prohibited in cosmetics in the EU.

Butylparaben

Butylparaben is a preservative that helps prevent microbial growth in shampoo. The European Chemicals Agency (ECHA) identifies it as an endocrine disruptor for human health and a substance of very high concern under EU REACH.

Butylphenyl Methylpropional

Butylphenyl methylpropional is a fragrance ingredient used to give shampoo a floral scent. The European Commission flags it for reproductive toxicity, and it is prohibited in cosmetics in the EU.

Imidazolidinyl Urea

Imidazolidinyl urea is a preservative that helps prevent microbial growth in shampoo. The Washington State Department of Ecology flags it as a formaldehyde releaser, which Washington restricts when intentionally added to cosmetics.

Ingredients in shampoo with transparency issues

Fragrance / Parfum

Fragrance blends give shampoo its scent or help mask the smell of other ingredients. Labels such as Fragrance, Parfum, or Natural Fragrance do not identify every ingredient in the blend, so Welpr treats them as a transparency issue: the label does not provide enough detail to assess the full mixture.

1,4-Dioxane

1,4-Dioxane is a potential manufacturing byproduct, not an intentionally added ingredient, so it generally won’t appear on a shampoo label. Names containing PEG or ending in -eth, such as laureth, can indicate ethoxylated ingredients whose manufacture may produce it, but they do not confirm contamination. It is flagged because IARC (WHO) classifies 1,4-dioxane as possibly carcinogenic to humans.

Ingredients shoppers may avoid for other reasons

Synthetic polymer

Synthetic polymers can thicken shampoo, stabilize the formula, or help condition hair. Some people prefer to minimize them, though this is not a health-hazard finding. Liquid, dissolved, and water-soluble polymers are not classified as microplastics.

Fragrance allergen

Fragrance allergens can be components of the ingredients used to scent shampoo. Those identified here are listed as fragrance allergens in EU Cosmetics Annex III and may matter if you have a known allergy or fragrance sensitivity.

Phenoxyethanol

Phenoxyethanol is a widely used preservative that helps prevent microbial growth in shampoo. Some shoppers prefer phenoxyethanol-free formulas as a personal ingredient choice.

Silicones

Silicones can help shampoo leave hair smoother, easier to detangle, and less prone to frizz. Some people avoid them because of environmental persistence, rather than a health concern.

Ethanolamines

Ethanolamines and their derivatives can help adjust shampoo’s pH or support cleansing and formula consistency, depending on the ingredient. Some shoppers prefer ethanolamine-free products as a personal ingredient choice.

Sulfate surfactant

Sulfate surfactants help shampoo lift oil and dirt so they can rinse away, and they often produce a generous lather. Some people avoid them because they find certain sulfate-based formulas drying or irritating, though the overall formula matters.

Isothiazolinone

Isothiazolinones are preservatives that help prevent microbial growth in shampoo. This family can cause skin sensitisation and allergic contact dermatitis, making it particularly relevant to people with a known allergy.

Azo dyes

Azo dyes add color to the shampoo formula, rather than serving a cleansing purpose. Some people prefer to avoid them because certain azo dyes are restricted in cosmetics, but those concerns relate to specific dyes rather than the whole family.

Choosing the best non-toxic shampoo for your hair type and need

Here's how we recommend picking the best non-toxic shampoo for you:

1. Start with a shampoo that meets the Welpr Standard. Every shampoo listed on this page already does.
2. Match the shampoo to your hair and scalp. Hair texture (fine, thick, straight, curly) and scalp condition (oily, dry, sensitive) change what a shampoo needs to do. Use the "Made for" filter above to narrow the list.
3. Narrow it further by the preferences that matter to you, such as fragrance-free, sulfate-free, or a shampoo bar instead of a bottle.
4. Pick the shampoo with the highest Performance score from what's left.

Here are our picks for non-toxic shampoo by hair type:

Best for fine hair

Fine hair is easily weighed down, so rich oils, butters, and heavy conditioning ingredients can leave it flat. A lightweight or volumizing formula that rinses clean usually works better.

Best for dry hair

Dry hair needs a shampoo that cleans without removing more oil than necessary. Look for gentle cleansers paired with moisturizing ingredients like glycerin, plant oils, or butters, and skip clarifying formulas made for oily hair.

Best for curly hair

Curly hair tends to be drier than straight hair, because the scalp's natural oils have a harder time traveling down a curl. Milder cleansers and added moisture help keep curls defined instead of frizzy, which is why many people with curls choose sulfate-free formulas.

Best for frizzy hair

Frizz usually comes from dry hair with a raised outer layer, which lets strands absorb moisture from humid air and swell unevenly. A moisturizing shampoo with gentle cleansers helps, especially when it's followed by a conditioner.

Best for men

Men are more likely to have shorter hair and an oilier scalp, so a lightweight shampoo that cleans thoroughly without heavy conditioning is often the best fit. Beyond that, choose based on your hair type and scalp rather than whether the bottle is marketed to men.

Best for oily hair

An oily scalp produces more sebum, so it usually does better with a shampoo that cleans more thoroughly, such as a clarifying formula. Heavy moisturizing shampoos can make roots look greasy sooner.

Best for sensitive scalp

A sensitive scalp reacts more easily to fragrance, some preservatives, and strong cleansers. Fragrance-free formulas are a good place to start, since fragrance ingredients are among the most common causes of allergic skin reactions to cosmetics, and it's worth checking the label for isothiazolinone preservatives too.

Best for locs

Locs need a shampoo that cleans the scalp and rinses out thoroughly, since residue can collect within the locked strands. Look for a formula that rinses clean without heavy conditioning, and consider a clarifying shampoo when styling products leave buildup.

Types of non-toxic shampoo

We cover two shampoo formats: shampoo bars and liquid shampoo. Dry and powder shampoos aren't included in our analysis (see "More about this analysis" above).

Non-toxic liquid shampoo

Liquid shampoo is still the most common format, and it lathers and rinses easily in any water. Because it's mostly water, it relies on preservatives, so it's worth checking the label for the flagged preservatives covered above.

Non-toxic shampoo bars

Bars contain little or no water, so many need fewer of the preservatives that account for several of the flagged ingredients in shampoo. They're also usually sold in paper or cardboard instead of a plastic bottle.

Shampoo bars come in two kinds, and the difference changes how they work on your hair:

That waxy residue is behind much of the "transition period" people describe when switching to a soap bar. It tends to show up as dull, heavy, or tangled hair in the first few weeks, especially in hard water, and it's a mineral residue rather than a sign that your hair is "detoxing." Many soap bar makers recommend an acidic rinse, such as diluted apple cider vinegar, to help. If you have hard water or want to skip the adjustment, a syndet bar is usually the easier switch.