Woolworths and Coles secrets exposed: Exactly how to use 'game-changing' tool to cut price of grocery shop

Woolworths and Coles shoppers have a new tool in their arsenal to keep their grocery shop as low as possible. Keeping across what items are on special at the major supermarkets is a lot of work.

But now there's a game-changing internet browser extension that does it for you. Most people might not realise the price cycles products go on and that's why Adam Williamson has decoded the secrets the supermarkets don't want you to know to help you save.

Yahoo Finance spoke exclusively with Williamson when he first launched the Coles extension which he has also developed for Australia's biggest supermarket, Woolworths.

"I think that's why people are loving this because it gives them the ability to see a trend and almost predict the price as well," he said.

So how do you use it?

Money-saving expert and Yahoo Finance contributor Joel Gibson has broken down the simple steps to capitalise off Coles and Woolies as they battle for your dollar.

How can I cut the cost of my grocery shop at Coles and Woolies?

Gone are the days of looking through catalogues and remembering when specials are on.

The browser plugin does all the hard work for you and you can predict when prices will come down or go up if there's a consistent trend.

What Gibson found is that Coles and Woolworths will usually have alternating weeks of discounts.

"When you've got Coles and Woolies both open in different tabs [online] and you've got this trend plugin downloaded, what you can do is you can say, 'I want a packet of Kettle Chips this week'," he said.

"These ones are six bucks. If I click in here, I can see that that's full price this week. They've been half-priced pretty much every second week. It's not a great time to buy these at Coles.

"But jump onto Woolies. Search for Kettle Chips, and you can see they're actually half-price this week."

He did another cost comparison that revealed a 520g box of Cadbury Favourites can sometimes be $22 and other weeks they are $11.

Electric toothbrushes have some of the biggest discounts, with the extension showing an Oral B Pro electric toothbrush pack can sometimes be $199 and other times $99.50.

You can save up to $9 depending on when you buy your nappies, $6.75 for tea bags, $7 on olive oil, and $36.50 on dishwashing tablets.

"People appreciate the sales cycle because they can now start to predict, 'Well, actually, if I just wait one more week, it's likely it's going to be half price again'," Williamson told Yahoo Finance.

Coles shoppers can download the extension here for Google Grome and here for Firefox users.

While the Woolies one can be downloaded here for Chrome and here for Firefox.

Plugin can help you 'laugh all the way to the bank'

Williamson told Yahoo Finance he initially built the extension just for himself, but it went viral on TikTok after he posted an example of how it works.

While there are already several ways to compare the current prices of products at Coles and Woolworths, Williamson felt it was better to make a standalone comparison for each supermarket.

"I find it a lot more interesting to compare the supermarket to themselves. Was it $2 a month ago? Is this special down from $6 actually an increase of $1?" he said.

It can also help you decode whether a deal is really a deal.

For example, if Coles tags an item saying the product is down 50 cents, customers can see if that is a markdown on a recent price, one from weeks ago or if it's gone through several price cycles.

Do you have a supermarket savings hack? Email stew.perrie@yahooinc.com

Gibson said this finally solves the big problem many Aussie shoppers face.

"I've been saying for years that people should shop at more than one supermarket and pick the specials each week at Coles or Woolies and Aldi... but it's not that easy, right?" he said.

"I know that most people don't have the time and energy to do that. What this does is it makes it really easy to do this online. So you can have one tab open for Coles online, one tab open for Woolies online.

He said you can find the best prices, do a click and collect order from each supermarket to avoid hefty delivery fees "and laugh all the way to the bank".

It can be difficult to know if you're getting a deal

Consumer advocacy group CHOICE recently found a quarter of Australian shoppers find it difficult to tell if a promotional tag in Coles, Woolworths and Aldi represents a genuine discount.

"This is particularly concerning considering many people are trying to make their grocery shop as affordable as possible in a cost-of-living crisis," Rosie Thomas, CHOICE director of campaigns, said.

At Coles, the hardest label for shoppers to understand was 'while stocks last', with CHOICE finding less than half could determine if there was a deal.

"To make things worse, even after asking Coles, CHOICE still doesn’t know if this is a discount or not,” Thomas said.

Woolworths has a label called 'prices dropped' slapped onto items across its supermarkets, which CHOICE revealed was also "confusing".

"Only half of respondents [said] they could quickly and easily tell if the product was discounted or not,” Thomas said.

H20 Coconut water was reduced from $6 to $4 in 2019, but still had a red 'prices dropped' label in store.

"We have doubts about whether a product that has been the same price for almost 5 years should be promoted as having a ‘dropped’ price. It’s no wonder consumers were confused as to whether it’s actually discounted or not,” Thomas added.

Get the latest Yahoo Finance news - follow us on Facebook, LinkedIn and Instagram.