I didn’t arrive at homemade shampoo quickly or directly. It was the end point of a longer journey that started with reading ingredient labels and feeling vaguely uneasy, moved through a succession of “better” options that mostly weren’t, and ended with a bottle of expensive natural liquid shampoo that was, genuinely, the worst thing I’d ever put on my hair. That was the moment I decided I could do better myself. Turns out I was right.

If you’ve found your way here, you might be at a similar point: fed up with what’s available, curious about making your own, and not entirely sure what “homemade shampoo” actually means or where to start. This article covers every option: liquid DIY shampoo, lye-based bars, and syndet bars. What each one involves, how they differ, and why I chose the option I did. By the end you’ll have enough to make your own informed decision rather than just following someone else’s.

If you’re new to making syndet bars and want to understand the full process before diving into a recipe, how to make shampoo bars at home covers everything from equipment to first-batch tips.

Or if you’ve been putting off making your own soap because of lye and six-week cure times, homemade soap without lye covers the syndet alternative, and everything you can make with it beyond just shampoo.

What “homemade shampoo” actually covers

The term gets used for three (IMO starkly) different things, and they’re not interchangeable.

Liquid DIY shampoo is a water-based formula containing surfactants, conditioning agents, andm critically, a broad-spectrum preservative. Because it contains water, bacteria and mould can grow in it, and a homemade liquid shampoo without a proper preservative system is a safety risk rather than a natural alternative. Making a genuinely safe liquid shampoo at home is possible, but it requires cosmetic-grade preservatives, pH testing, and a reasonable understanding of emulsion chemistry. For some people this is the right path and if you have a strong preference for liquid format and are willing to learn the preservation side of the process, it’s achievable. It’s just more involved than most “homemade shampoo” content suggests.

Lye-based shampoo bars are traditional cold-process soap bars made with sodium hydroxide (aka lye) which reacts with oils in a process called saponification to produce soap. The chemistry works and lye-based soap has been made safely for centuries. But for shampoo specifically, there are real limitations: the naturally high pH of soap (around 9–10) disrupts the hair cuticle and can cause frizz, dryness, and a notorious waxy buildup, particularly in hard water, where soap reacts with mineral ions to form an insoluble film on the hair. Lye also requires proper safety equipment and careful handling, a four-to-six week cure period, and dedicated equipment that shouldn’t go back to food use. None of this is insurmountable, but it’s a decent barrier for someone who just wants to make a better shampoo in their kitchen.

Syndet bars are what this site is about, and possibly what you haven’t heard of yet. Syndet is short for synthetic detergent…a name that sounds less natural than it is, since the primary surfactant in most syndet bars (SCI, or sodium cocoyl isethionate) is derived from coconut oil. Syndet bars are built around surfactants rather than soap, using a melt-and-mix process rather than a chemical reaction. No lye. No saponification. A pH that sits naturally close to the hair and scalp’s own environment. A seven-day cure rather than six weeks. And performance in hard water that soap-based bars simply can’t match.

Why I chose syndet bars — and how I got there

My journey to homemade shampoo didn’t start with bars at all. It started with SLS.

Sodium lauryl sulphate is the surfactant in most mainstream shampoos, and it’s genuinely effective because a powerful cleanser that produces the dense lather most people associate with a thorough wash. The problem is that it’s indiscriminate. It strips sebum, dirt, product residue, and the scalp’s own lipid barrier in roughly equal measure. My hair has always been genuinely greasy so I hadn’t realised my hair was probably just rebounding with excess oil production.

But I wanted to do better so I started looking for alternatives. SLS-free shampoos. “Natural” options. Retail shampoo bars. I bought a succession of bars from various sources and found them difficult to find, expensive, inconsistent in quality, and, in a couple of cases, clearly soap-based products that left my hair worse than before. I tried liquid shampoos marketed as natural and plant-based that delivered the kind of results that make you wonder what you were paying for. The last one was a premium-priced bottle with a long list of botanical extracts on the label and very little else to recommend it and it was the moment I stopped looking for the right product and decided to make my own instead.

I was ready to try lye-based cold process bars. I’d done the research, I understood the process, and I was prepared for the complexity. Then I found syndet bars. The first time I washed up after making a batch (hot water in the mixing bowl, watching genuine foam appear immediately!) I knew I’d found what I’d been looking for. Not because it was easier than lye (though from a theoretical perspective because I never did commit to lye, it was), but because it worked. First wash. No transition drama. Hair that felt clean in a way that actually meant clean.

That was the beginning of Batch & Bubble.

How each option compares

	Liquid DIY	Lye-Based Bar	Syndet Bar
Preservative required	Yes — essential	No (anhydrous)	No (anhydrous)
Lye required	No	Yes	No
Safety equipment	Standard kitchen	Goggles, gloves, ventilation	Face mask only (for SCI powder)
Cure time	N/A	4–6 weeks	7 days
pH	Formulator-controlled	Naturally high (9–10)	Naturally closer to hair pH
Hard water performance	Depends on formula	Poor (soap scum)	Good
Complexity	Moderate–high	Moderate	Low–moderate
Format	Liquid	Solid bar	Solid bar

The right option depends on what matters most to you. If you’re committed to liquid format and willing to learn preservation properly, liquid DIY is achievable. If you want the closest-to-nature, most minimally processed bar and are comfortable with the lye process and longer timeline, cold process has its advocates. If you want something that’s genuinely beginner-accessible, performs well from the first wash, and doesn’t require caustic chemistry in your kitchen, syndet is where I’d point you.

Why syndet specifically works

The core of a syndet shampoo bar is a gentle surfactant system rather than soap. SCI produces a rich, creamy lather, cleans effectively without stripping, and is mild enough for daily use. It’s the same class of ingredient used in professional and dermatologist-recommended formulas, derived from coconut oil, and significantly gentler than SLS at the concentrations where it does its best work.

The pH sits naturally in a range much closer to the hair and scalp’s own environment than soap does, which means less cuticle disruption, less frizz, and better hard water performance. The what pH does to your hair article covers the mechanism in detail if you want the science.

Syndet is also, IMHO, the best shampoo for sensitive scalps.

It also costs a fraction of what you’d pay commercially. The full cost breakdown shows how a batch of five bars typically comes to under $4 AUD per bar in ingredients which is significantly less than most commercial bars cost individually, made from ingredients you can name and understand. Retail bars are not exorbitant given all the costs they have to cover but when you’re DIYing, you’re not paying for chemical testing, marketing, packaging, retailer market up etc.

Is syndet shampoo only available as a bar?

No. Syndet simply means synthetic detergent. The same surfactant system that makes a syndet bar can be formulated as a liquid shampoo, and commercial liquid shampoos use surfactants (including SCI, CAPB, and others) rather than soap. The difference between a commercial liquid shampoo and a homemade syndet bar isn’t the surfactant chemistry, it’s just the format and what’s added to support that format.

For my household, a bar is the right choice: no preservative required in an anhydrous formula, less plastic waste, concentrated performance, and a making process that works in a home kitchen without specialist equipment.

Read more about what makes a solid shampoo bar and what the options are.

Where to start if you’re ready to make your own

The Batch & Bubble shampoo bar range covers three hair types and several clay variations:

By hair type:

• Oily hair: DIY oily hair shampoo bar recipe — the original formula, high SCI, high kaolin clay
• Normal hair: normal hair shampoo bar recipe — balanced formula, the most broadly applicable starting point
• Dry hair: dry hair shampoo bar recipe — gentler cleansing, higher jojoba, lower clay

Clay variations — once you’ve made the base formula and want to experiment with colour:

• Green clay and rosemary: green clay and rosemary shampoo bar — for oily hair, stronger absorption, natural green colour
• Brazilian purple clay: purple clay shampoo bar — for normal hair, mauve-grey tone, possibly gentler than kaolin

All recipes use the same melt-and-mix process with no lye, a seven-day cure, and ingredients sourced from Australian cosmetic suppliers. The shampoo bar recipe without lye article explains the syndet versus soap distinction in more detail if you want to understand the format before committing to a batch.

If you’re ready to complement your shampoo bar with a conditioner bar (and once you’ve made one bar, I’d reckon you very likely will be), the DIY conditioner bar recipe uses the same approach applied to conditioning rather than cleansing.

If you don’t know which recipe to start with for your hair, take the Batch and Bubble hair type quiz. Three questions, results straight away, and if you choose to, you can have your tailored recipes delivered directly to your inbox:

What to expect from the first wash

The transition from commercial shampoo to a syndet bar is gentler than switching to a lye-based bar, but there’s still an adjustment period for most people. The shampoo bar transition period article covers what to expect and how long it lasts. For genuinely oily hair the adjustment is more pronounced; for normal to dry hair it’s usually mild.

If something isn’t working after the first few washes, the shampoo bar troubleshooting guide is the place to start rather than assuming the format isn’t for you.

Neets is a Brisbane-based home formulator and the founder of Batch and Bubble. She has an applied science degree, makes all her own bars, and considers that terrible bottle of natural liquid shampoo to have been, in retrospect, the best money she ever spent.