what is laundry detergent?

Wondrous laundry detergent. 

You’re the unsung hero of smelly socks, dirty sheets and that T-shirt you insisted on wearing for one more day than you probably should. 

But what exactly is this magical substance that transforms stained laundry into wearable, sniffable clothing? And are powders, liquids and capsules all the same stuff? Let’s find out - and spoiler alert: it’s not magic (but here at smol we reckon it’s close)!

so, what exactly is laundry detergent?

In its simplest form, laundry detergent is a mix of ingredients designed to break up dirt, banish stains and make your clothes smell lovely (or neutral, if scented laundry isn't your thing). 

Long ago, people used bar soaps made from animal fats and ashes but NOW we enjoy high-tech formulations with enzymes and surfactants. There are liquids, powders and capsules, each promising to keep your whites white and your colours bright

what does laundry detergent do?

In a nutshell, it cleans! And here’s how:

1. breaks up dirt.

Detergents contain surfactants that act like tiny bouncers. They grab grease, dirt, and grime, pulling them away from your clothes. No rubbing, no scrubbing, no problem.

2. keeps it clean.

Without detergent in the water, dirt would leave your clothes mid-wash, only to sneak back on again at some point. Detergents contain anti-redepositing agents to make sure the grime stays suspended in the water until it’s drained away. Bye-bye, gunk.

3. enzyme action.

Enzymes are found in biological detergents (bio for short) and they’re awesome at getting out stains. Non-bio detergents won’t have them. Enzymes even come in with different types that work on specific stains. smol bio capsules have FIVE powerful enzymes including one BRAND NEW superhero to tackles body odour and body oil discolouration along with all the invisible stains we leave on our clothes day in and day out. It brings next level cleaning to our bio. 

4. adjusts to your water.

Hard water? No problem. Detergents have water softeners that help everything work better.

5. smells good.

Most detergents are fragranced, leaving your clothes smelling like a meadow at sunrise (or nothing at all, if fragrance-free is more your vibe).

how does it work?

While every brand has its own “secret recipe,” most detergents include:

• Alkalies: for grease-busting.
• Surfactants: to lift dirt away.
• Enzymes: for targeted stain fighting.
• Optical Brighteners: to reflect light and give a colour boost. 

So are laundry powder, liquid and capsules all the same? Well nope…

powder.

Think powder, think old school. It often contains more alkalies (for grease-fighting) and is good for hard water areas when paired with a fabric conditioner. It’s also lightweight on the wallet.

BUT, it doesn't dissolve well in cooler washes, so if you’re a cold-wash fan, you might find residue hanging out on your clothes. And on top of that powder has been shown to release almost 3 x more plastic microfibers from clothing during a wash than a liquid or capsule detergent ¹

liquid.

Laundry liquid is a multitasking mate who’s good at everything.

It’s great for pre-treating stains and works brilliantly in cold washes and mixed loads because it dissolves instantly and is perfect for tackling oily stains. BUT watch out for those dinosaur big brands like Ariel, Persil and Fairy who STILL put their laundry liquid in single-use plastic bottles. 

Remember, it’s 2025… smol made laundry liquid refillable. A bottle-for-life and refill cartons are all you need.

capsules.

They’re sleek, efficient and always on point. If you love the easy-life or have a knack for overpouring liquid - these are for you. Just toss one in, and you’re done; they’re pre-dosed so you’ll never use too much (or too little). Capsules really are convenience kings AND you can get a FREE TRIAL with smol. Happy days.

so in summary…

Laundry detergent is your wardrobe’s best friend. It lifts dirt, fights stains, and keeps your clothes looking, feeling, and smelling fab. It’s come a long way since soap bars and boiling water and now it’s as high-tech (and as easy) as you want it to be.

Happy washing!

more from smol.

Does smol get laundry clean at 20?
What are the three sections in the washing machine drawer?
What's the difference between bio and non-bio?
Top 5 ways to remove chewing gum from clothes.
How to remove mould from your washing machine door seal.

¹ PLoS One 2020 Jun 5;15(6):e0233332. doi: 10.1371/journal.pone.0233332. eCollection 2020.

Microfiber release from real soiled consumer laundry and the impact of fabric care products and washing conditions Neil J Lant 1, Adam S Hayward 1, Madusha M D Peththawadu 2, Kelly J Sheridan 2, John R Dean 2