Ever wondered why your hands don’t become clean when you rinse them under water? This is due to a substance called a surfactant. Both soap and detergent are surfactants, meaning they break surface tension to help water penetrate surfaces and connect with things it normally wouldn’t — like oil. Without surfactants, water would just slide over oil like it’s not even there. But what exactly sets soap apart from detergent?

Table of Contents

• Soap vs Detergent
• How Soap Is Made
• How Detergent Is Made
• Why Use Detergents?
• Environmental Impact
• Is Soap Always Better?
• Quick Comparison Chart
• Which Should You Choose?

Soap vs. Detergent

Both soap and detergent do the same job: they clean. They’re both surfactants that help water mix with oil and dirt so you can rinse it all away. But the way they’re made, their environmental impact, and how they perform in different conditions vary quite a bit.

Here’s a quick breakdown:

• Soap: Made by reacting natural oils with an alkali (like sodium hydroxide or potassium hydroxide).
• Detergent: Often synthesized in a lab and can be derived from natural or petroleum-based sources. They’re usually more complex and versatile than soap.

How Soap Is Made

Soap has been around for millennia — one of humanity's oldest chemical reactions. It’s made through a process called saponification. Here’s how it works:

• Take a natural fat or oil like coconut, olive, or hemp oil.
• Add a strong alkali such as sodium hydroxide or potassium hydroxide.
• Combine and the reaction produces soap, glycerin, and water.

Read more: What Is Castile Soap?

How Detergent Is Made

Detergents, on the other hand, are more modern creations. They were developed during World War I and World War II when the oils used for making soap were in short supply. Scientists figured out how to create cleaning agents that didn’t rely on plant-based oils [1].

Unlike soap, detergents are made through multi-step processes in a lab. They can be derived from both natural substances (like coconut oil) and synthetic materials (like petroleum derivatives). This makes detergents more versatile than soaps, but it also means they can have a larger environmental footprint.

Why Use Detergents?

Detergents have a few advantages over soap:

• They tend to perform better in hard water (which has a lot of minerals like calcium and magnesium). Soap tends to form films or deposits in hard water, while detergents stay stable and effective.
• They’re more customizable. You can tweak detergents to be super tough on grease or ultra-gentle for delicate fabrics.

But not all detergents are created equal. Many commercial detergents contain harsh synthetic ingredients and petroleum-based chemicals that aren’t so great for you or the planet. That’s why we’ve created a better option with Sal Suds — our biodegradable, plant-based detergent that’s tough on grime but gentle on the environment.

Soap vs. Detergent: Environmental Impact

One of the biggest differences between soap and detergent is their environmental impact:

• Soap: Made from renewable plant-based oils and is fully biodegradable. It’s a friend to both your skin and the planet.
• Detergents: Can be made from natural or synthetic sources. Some detergents are biodegradable, but many aren’t. And those derived from petroleum tend to not be eco-friendly.

Is Soap Always Better?

So, is soap better than detergent? The answer isn’t that simple. There are poorly made soaps out there. For example:

• Harsh soaps made with short-chain oils can be rough on the skin.
• Poorly balanced soaps may have leftover alkali, resulting in a product that’s too alkaline (high pH) and potentially irritating.

And there are also excellent detergents — like our Sal Suds Biodegradable Cleaner — that are plant-based, biodegradable, and super effective at cutting through grease and grime without leaving any residue. The key is to look at the ingredients and the impact of the product.

Quick Comparison Table: Soap vs. Detergent

Final Thoughts: Which Should You Choose?

So, what’s better: soap or detergent? It depends on what you’re cleaning and what matters most to you.

• For your body: Stick with true soaps like our Castile Soap. They’re gentle, natural, and eco-friendly.
• For tough household cleaning: Our Sal Suds detergent is your best bet. It’s biodegradable and incredibly effective.

Whether you choose our Castile soap or our Sal Suds, you can trust that you’re getting a product that cleans the body and home responsibly.