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Trader Joe's

Peppermint Multi-Purpose Castile Soap

Shampoo / Low-lather cleanser, non-foaming

  • Shampoo
  • Sulfate-free
  • Silicone-free
  • Cruelty-free · PETA-listed
Size16 fl oz
Price$5.99 Good valueseen at one store · 16 oz
Price / oz$0.37/ozat 16 oz
Where to buy1 store

Add it to your products. We’ll tell you if it’s ever recalled.

Scent:

No added fragrance on the label, but it contains scenting botanicals. Essential oils have a smell even when they are not labelled as fragrance.

Manufacturer page: traderjoes.com

Personal fit

Is this right for you?

Complete the consultation to see how well this product fits your hair and your goals. With 6,000+ products in our library, we can match you to the right ones.

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  • Every product matched against your hair across the 22 factors we check.
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  • Find products that do the same job at a lower cost.
  • Your goals, scalp, damage history, water, budget, and scent preferences all shape your plan.

$49 with 60 days of follow-up questions and plan updates

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Lower cost than most shampoos

$0.37/oz at 16 oz, less than 94% of the 1544 shampoos , which mostly run $0.79–3.04/oz.

Price and stores

Great for

no fragrance (parfum) on the label, but still scented
Colour-treated hairthat fades faster in a sulfate wash
Protein-sensitive hairthat stiffens when protein is added
Frequent washerswho want gentler cleansing
Curly-method routinesno sulfates and no water-insoluble silicones
Coarse or dry hairthat absorbs everything you give it

Maybe skip if

this product has a scent
Oily scalp or fine hairthat gets weighed down
A squeaky-clean feelthis deliberately leaves conditioning behind
Stretching wash dayswaxes stay until a detergent wash removes them
Foam-heavy washesit barely lathers
Hair that needs proteinthere is none in this list

How much cleansing you need depends on how fast your scalp gets oily, how much product you layer and your water. The consultation works that out.

What the formula actually does

Read from the label, not the marketing

Each row says where it comes from: F means we derived it from this product’s own ingredient list, S means it is a claim the brand makes that the formula neither confirms nor contradicts.

Cleansing strength None

No detergent. The conditioners do the cleaning.

Expected lather Little

Very little foam; it is worked through rather than lathered.

Slip and detangling Some

Some slip, mostly from esters or silicones rather than conditioners.

Water-binding (humectants) None found

No humectants, so nothing here pulls water into the hair.

Scalp active None

No over-the-counter scalp active.

Hard-water defence None

No chelating agent in the list.

Needs detergent to remove Yes

Water-insoluble silicones or waxes: a detergent wash is what removes them.

Protein None

No protein or amino acids in the list.

Fragrance None listed

No fragrance is listed.

from the formula stated by the brand reported by reviewers Scale: 1 dot low · 5 dots high, within this product type.

Ingredients that matter

The ingredients that change a decision

The workhorse ingredients, plus anything lower down that changes a decision. The chips name what an ingredient does. They are not safety scores, and no ingredient here is rated good or bad on its own.

IngredientWhat it doesWhy it mattersChip
WaterWATER (AQUA) solvent The base everything else is dissolved in Neutral
Olea Europaea (Olive) Fruit Oil oil Coats and softens the strand Softens
Cocos Nucifera (Coconut) Oil oil Coats and softens the strand Softens
Potassium Hydroxide pH adjuster Fine-tunes the pH pH balancer
Mentha Piperita (Peppermint) Oil botanical extract A trace plant extract Fragrance
Mentha Arvensis Leaf Oil fragrance The scent Fragrance
Cannabis Sativa (Hemp) Seed Oil oil A small amount of oil for softness Softens
Simmondsia Chinensis (Jojoba) Seed Oil emollient A softening touch, low in the list Buildup
What the list leaves out, and what it carriesNo sulfates, silicones, or drying alcohols. Protein-free: this is built for moisture rather than for strengthening. Contains heavier butters.
Full ingredient list (12)

In the US, ingredients above 1% are listed from most to least. Below 1% they can appear in any order. Each note keeps three things apart: what the ingredient generally does, its role in this type of product, and what its position can tell you.

  • 1 Water · WATER (AQUA)
    General function

    The base of almost every rinse-off and cream hair product. It carries everything else and is normally the first ingredient on the label.

    Leading ingredient

    Listed in the first three ingredients, it is likely a structural part of this formula.

    • solvent
  • 2 Olea Europaea (Olive) Fruit Oil
    General function

    A heavy, coating oil traditionally used for deep conditioning.

    Leading ingredient

    Listed in the first three ingredients, it is likely a structural part of this formula.

    May suitDry, coarse, or high-porosity hair

    Coats the surface and slows water leaving the strand, which is usually what coarse hair that dries out fast is missing.

    May suitFrizz-prone, damaged, or high-friction hair

    A thin oil layer lowers friction between strands and flattens the raised cuticle that scatters light and catches on its neighbours.

    May not suitFine or easily flattened hair

    Near the top of a list an oil is weight before it is anything else, and fine hair shows that first at the roots.

    • oil
    • emollient
  • 3 Cocos Nucifera (Coconut) Oil
    General function

    One of the few oils small enough to move into the strand, which is why it is used for pre-wash treatments. It can feel heavy or stiff on protein-sensitive hair.

    Leading ingredient

    Listed in the first three ingredients, it is likely a structural part of this formula.

    May suitDry, coarse, or high-porosity hair

    Because it penetrates rather than sits on top, it works on hair that loses water through a worn cuticle instead of only slowing evaporation from the surface the way a non-penetrating oil does.

    May suitFrizz-prone, damaged, or high-friction hair

    A thin oil layer lowers friction between strands and flattens the raised cuticle that scatters light and catches on its neighbours.

    May suitVery dry or highly damaged hair

    The exception to the class read: lauric acid is small and linear enough to enter the shaft rather than only coat it, and in comparison testing coconut oil was the one that reduced protein loss from washing on both undamaged and damaged hair.

    International Journal of Trichology
    • oil
    • emollient
  • ▾Below about here, the order stops meaning much. These are usually used at 1% or less.
  • 4 Potassium Hydroxide
    General function

    A strong base used in trace amounts to set pH; it is fully neutralised in the finished product.

    Estimated lower-concentration zone

    It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

    DependsFrizz-prone, damaged, or high-friction hair

    pH adjusters are how a formula is brought to a chosen acidity, and an acidic formula keeps the cuticle lying flatter than an alkaline one. Which way this one moves the pH depends on the formula, and the finished pH is not on the label.

    PubChem
    • pH adjuster
  • 5 Mentha Piperita (Peppermint) Oil
    General function

    Peppermint essential oil, used for scent and the cooling feeling on the scalp.

    Estimated lower-concentration zone

    It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

    May not suitFragrance-sensitive routines

    Essential oils are fragrance. Several carry constituents on the EU list of declared fragrance allergens, so a label with no fragrance line can still be a scented product.

    • botanical extract
    • essential oil
    • fragrance
  • 6 Mentha Arvensis Leaf Oil
    General function

    Cornmint oil, used for a cooling sensation and mint scent.

    Estimated lower-concentration zone

    It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

    May not suitFragrance-sensitive routines

    Declared fragrance. On a fragrance-sensitive routine this is the line that decides it, wherever it sits on the label.

    • fragrance
    • botanical extract
  • 7 Cannabis Sativa (Hemp) Seed Oil
    General function

    The oil pressed from Hemp (Cannabis Sativa). It is one of the lighter plant oils, absorbing faster and leaving less residue.

    Estimated lower-concentration zone

    It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

    May suitDry, coarse, or high-porosity hair

    Coats the surface and slows water leaving the strand, which is usually what coarse hair that dries out fast is missing.

    May suitFrizz-prone, damaged, or high-friction hair

    A thin oil layer lowers friction between strands and flattens the raised cuticle that scatters light and catches on its neighbours.

    • oil
    • emollient
  • 8 Simmondsia Chinensis (Jojoba) Seed Oil
    General function

    Not chemically an oil: about 97% of it is liquid wax esters, which is why it resists going rancid and sits close to the scalp's own sebum. It smooths without a heavy finish.

    Estimated lower-concentration zone

    It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

    May suitDry, coarse, or high-porosity hair

    Coats the surface and slows water leaving the strand, which is usually what coarse hair that dries out fast is missing.

    May suitFrizz-prone, damaged, or high-friction hair

    A thin oil layer lowers friction between strands and flattens the raised cuticle that scatters light and catches on its neighbours.

    May suitMaximum-hold styling

    A wax holds by staying solid on the strand, which gives grip and separation rather than a set film that cracks.

    • emollient
    • light ester
    • oil
    • wax
  • 9 Tocopheryl Acetate
    • antioxidant
    • vitamin
  • 10 Elaeis Guineensis (Palm) Kernel Oil
    • oil
    • emollient
  • 11 Citric Acid
    General function

    Used to bring the product to a slightly acidic pH, which helps the cuticle lie flat. It is almost always near the end of the list.

    Estimated lower-concentration zone

    It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

    May suitBuild-up-sensitive routines

    Holds hard-water minerals in solution so they rinse away instead of depositing on the hair.

    May suitFrizz-prone, damaged, or high-friction hair

    The acid side of pH adjustment, and the reason it matters is measured: alkaline formulas raise the fibre's surface negative charge, increase friction between strands and lift the scales, while lower-pH ones do the reverse.

    May suitGray, silver, or brass-prone hair

    Where a warm cast comes from water minerals rather than from the hair itself, holding those metals in solution is what removes it.

    International Journal of Trichology
    • pH adjuster
    • hard-water chelator
  • 12 Sodium Chloride
    • salt
    • thickener

What the whole list adds up to

  • 5 oils
  • 5 emollients
  • 2 pH adjusters
  • 2 botanical extracts
  • 2 fragrances
  • 1 solvent
  • 1 essential oil
  • 1 light ester
  • 1 wax
  • 1 antioxidant
  • 1 vitamin
  • 1 hard-water chelator
  • 1 salt
  • 1 thickener

Ingredient list captured 2026-10-03. Formulas change, so check the package in your hand when an ingredient matters to you.

Price · 16 oz

Seen at $5.99 1 store · checked Oct 3
Good value under $33 Under $2.05/oz it costs less than three-quarters of the 8 products we score as doing the same job

Usually a good value. Most stores sell it under the $33 line, and products that do this job typically go for about $46 at this size.

Show the price ladder
Where we’ve seen it1 listing · 1 store

Sorted by price per ounce. Dated observations from our research, not live prices. Direct store pages, no affiliate links. We don’t sell this product.

How we work this out
  1. 16 oz is the size stores list most often; every comparison on this page is made at it. Other sizes are shown in the Sizes row and the store list.
  2. Seen at $5.99 is the price we have observed for the 16 oz. We need three stores before we call a price commonly seen.
  3. Good value under $33 comes from the 8 products we score as doing the same job as this one. A quarter of them cost less than $2.05/oz; at 16 oz that is $33. Under that line you are paying less than most of them.
  4. About $46 is what those same products typically cost at this size: the midpoint of their prices per ounce, scaled to 16 oz.

Formula

Formula score
3 of 10

It costs less per ounce than most shampoos, and the formula leaves out working detergent system, which a shampoo is usually built around.

How the score is counted
  • Costs less per ounce than 94% of the 1544 shampoos we’ve priced
  • No working detergent system in the formula
  • No slip for detangling either
  • Drugstore tier, sold at Specialty beauty
  • A working detergent systemWhat actually removes oil and product.3 pts
  • Slip for detanglingReduces the force it takes to comb wet hair.2 pts
  • A humectantBinds water into the hair.1 pt
  • A hard-water chelatorBinds the minerals that dull hair in hard water.1 pt
  • A pH adjusterBrings the formula to the acidic pH hair prefers.1 pt
  • No detergent-dependent filmNothing that needs a clarifying wash to remove.1 pt
  • Fragrance kept out of the top eightScent as a finishing touch, not a major share.1 pt

The formula score measures completeness for the job: a weighted share of the systems this product type is usually built around that we find in this list. It does not rate how well the product works or its quality, and it never compares across product types.

Does the same job

Formulas that do the same things (cleanse, condition, coat or hold) for less per ounce. Scent, texture and where you buy them can still differ.

John FriedaLighter feel Volume Lift Dry Shampoo $3.14/oz $2.77/oz more
  • Sulfate-free
  • Gentle cleanse
  • Curly method
· Close function
Function
  • Oils and butters
  • Protein
  • Film formers
Also
  • Masstige tier
  • 5.1 oz bottle
Compare
Nature Skin ShopClose function Apple Cider Vinegar Clarifying Shampoo Bar $10.00/oz $9.63/oz more
  • Fragrance-free
  • Unscented
  • Sulfate-free
Function
  • Slip and detangling
  • Water-binding (humectants)
  • Needs detergent to remove
Also
  • Unscented
  • Masstige tier
  • 2 oz bottle
Compare
Alikay NaturalsLowest cost per oz Caribbean Coconut Milk Shampoo $2.62/oz $2.25/oz more
  • Sulfate-free
  • Protein-free
  • Gentle cleanse
· Related function
Function
  • Slip and detangling
  • Water-binding (humectants)
  • Film formers
Also
  • Coconut scent
  • Masstige tier
  • 8 oz bottle
Compare

See more alternatives in the product library

These products do a similar job. We haven’t matched them to you. Find the one that fits your hair, routine and budget

Built for curly to coily hair

Final decision

Should you buy it?

A solid pick for the hair it suits
Best user

People sensitive to fragrance, looking for a formula with no added fragrance and washing without sulfates

Biggest tradeoff

Worth skipping for anyone sensitive to fragrance, oily scalps and fine hair, or anyone who wants a squeaky-clean feel

Best alternative if not

Nothing in our library matches it closely at a lower price.

We do not sell products or take placement fees. This page states what the formula and the prices show; the consultation is what matches it to a person.

Claims check

What the brand says, and what the formula shows

Claims are quoted from the brand. We mark a claim supported, partly supported or conflicting only when the ingredient list speaks to it. Everything else stays "stated by the brand". That isn’t a criticism: most claims can’t be checked from a label.

0
SupportedBacked by ingredients
0
Partly supportedSome supporting logic
2
Stated by brandNo clear evidence
1
Potential conflictFormula works against claim
Can use as body wash, shampoo, household cleaner or laundry cleaner

Heavy emollients sit high in the list, which usually works against lift.

  • Olea Europaea (Olive) Fruit Oil
  • Cocos Nucifera (Coconut) Oil
  • Cannabis Sativa (Hemp) Seed Oil
Potential conflict

Likely to weigh hair down.

Natural low-lather soap

This is a marketing claim; an ingredient list cannot speak to it.

—

Stated by brand

Can’t be confirmed from label.

No synthetic dyes, sulfates, parabens or phthalates

This is a marketing claim; an ingredient list cannot speak to it.

—

Stated by brand

Can’t be confirmed from label.

How to read this

We look at the first 10–15 ingredients and what they do in a formula, not at the marketing. If the list doesn't speak to a claim, we don't assume.

More from Trader Joe's

How this page was made

  • Everything above comes from our researched product record: identity, the ingredient list as printed, the brand's own claims, dated prices and review themes our researchers wrote in their own words. No part of this page is written by hand for one product.
  • The value band is a fixed label over two stored numbers: this product’s cost per ounce as a percentile of every product of this type we have priced, each at the size it is most often sold in, and how many products we score as doing the same job cost at least a quarter less per ounce.
  • Both scores out of ten are defined on this page. The formula score is completeness for the job, computed from a fixed per-format checklist shown beneath the gauge; the price score is cost per ounce against every product of this type we have priced.
  • The "Is this right for you?" panel reads only your own consultation answers, and it applies exactly the filters our recommendation engine applies. It is computed when you load the page and is never stored on it.
  • 2 sources consulted for this product (1 manufacturer or regulatory, 0 retailer, 1 editorial), last checked 2026-10-03.
  • Ingredient references are linked for 3 of 8 product-aware annotations on this page. Fit notes are general formulation guidance. They aren’t a verdict on the finished product or on you.
  • We haven’t tested this product in a lab, and we don’t physically test your hair. Formula readings come from the ingredient list. Claims about how it behaves are labelled as the brand's.
  • Ingredient order tells you relative amount only above roughly 1%. Prices are what we saw on the dates shown and can change.
  • Ingredient names link to our ingredient library, where each entry shows what it does, which product types use it, and where it usually sits on a label across everything we have researched.
  • This is cosmetic information, not medical advice, and nothing here diagnoses or treats a health condition.
  • Formula readings: derivation v23. Record last updated 2026-10-03.

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