Think petrol is expensive? These everyday items actually cost more per litre!

Unless you drive an electric car, the price of petrol is your foremost concern as a motorist. It affects your vehicle running costs, and for some car owners, dictates how much they have left to spend on other things.

A litre of RON 95 currently retails for $2.85 a litre (before discount). If you pump 40 litres today, it would cost you $114. A while back, when prices were around $3.35 per litre, the same tankful cost $135.20.

The difference, $21.20, seems minimal, but not if you needed to fill up weekly. That adds up to an additional $84.80, which is hardly small change when you consider the equivalent in groceries.

Petrol is still expensive. But if you want to save money, it may be time to cut back or consume less of these items, which actually cost more per litre!

1. Shampoo

A shorter haircut keeps you cooler and helps you use less shampoo

Yes, shampoo is surprisingly expensive, even if you buy mass market brands that come in large bottles.

A 720ml bottle of Head & Shoulders Anti-Dandruff Shampoo in FairPrice is listed for $12.95. But even if that bottle lasts you a long time, it still works out to around $17.99 per litre.

Yikes. That's over 6.3 times more expensive than a litre of fuel.

2. Laundry detergent

Detergent is surprisingly expensive, so washing full loads reduces wastage

They say you should only activate the washing machine when you have a full load of clothes to wash. Apart from saving electricity, this will help you cut down on detergent usage.

Like shampoo, laundry detergent comes in big containers. A 2.7-litre bottle of Persil goes for around $12.55, which works out to around $4.65 per litre.

Not as costly as shampoo, but still, every bit saved helps your bottom line.

3. Bubble tea

It's a sacrifice, but forgoing bubble tea is worth the health benefits

Cool, sweet milk blended with tea and perhaps brown sugar, a healthy dollop of tapioca pearls, in a cup filled with ice cubes. Ahh bubble tea. It's a dessert and pick-me-up at the same time, and some of us can't live without it.

But how much does this habit cost? A medium-size, 485ml cup of Koi Golden Bubble Milk Tea, for instance, is $4.30. That's $8.87 per litre.

If you can't live without bubble tea, just remind yourself that consuming too much of it could lead to diabetes, and that could cost you more than just money.

4. Hand sanitiser

It's useful in a pinch, but if you're pinching pennies, washing your hands is a better bet

By now, most of us are used to either washing our hands regularly, or religiously applying hand sanitiser several times a day.

Those little bottles, however, come at a significant cost. A 50ml bottle of Dettol Hand Sanitiser is $3.50, which works out to a whopping $70 per litre.

Consider washing your hands instead. Or if no facilities are available, try your best to not touch your face.

5. Shaving gel/foam

Using a shaving soap and a double-edge razor instead of shaving gel and a cartridge-type razor can save you even more money in the long run

Since shaving is routine for most guys, we often don't consider how much the supplies we need can impact our wallet.

The least expensive can of Gillette shaving foam, for example, is $3.90. Sounds reasonable. But that only buys you 200ml, so the price per litre is $19.50.

There are ways to save, of course. Shaving less often is one, but if good grooming matters, you could consider investing in a shaving brush and proper shaving soap. The latter lasts longer and is better for your skin, too.

6. Soju

Instead of drinking every day, save these bottles for celebrations - doing so will make each occasion feel even more special

Alcohol comes in many forms and soju is one of the most popular types today. A 360ml bottle of Jinro Green Grape is usually $12.90 a bottle, but the price drops to $9.90 if you buy two.

At $9.90 for 360ml, that still comes to $27.50 per litre. Even if you drink at home, it's best to be careful with this one, as its drinkability makes it very easy to consume a lot before you realise it.

And it goes without saying that you should never drink and drive.

7. Beer

Considering how much it can cost, it's no surprise that beer is sometimes referred to as 'liquid gold'

Since soju and other harder liquors are even more expensive, good old beer is the more cost-effective choice, right?

Not to promote alcohol consumption, but yes. When it's not on sale, a pack of 10 320ml cans of Tiger retails for about $26.50. Do the math and this works out to $8.28 per litre.

That doesn't sound too bad. But remember, everything in moderation!

Wondering how to save fuel and reduce your running costs? Check out these stories

Seven ways to reduce car running costs

Must-know tips for cheaper car maintenance

Five sure-fire ways to improve your car's fuel economy

Beyond sticker shock: Running costs first-time car owners must consider