The Albanese government is looking to introduce "substantial" fines for supermarkets who breach a strengthened unit pricing code, which gives consumers timely price comparisons.

The practice of "shrinkflation" - when a product is sold for the same price though its size has been reduced - is in the government's sights as households across the country struggle with a cost-of-living crisis.

Prime Minister Anthony Albanese said Labor was also making changes to Australia's consumer watchdog to ensure it remained a "tough cop on the beat".

"We are cracking down on supermarkets to help Australians get a fair deal at the checkout," he said.

The government will consult on the code on areas including improving readability and visibility of unit pricing in stores and addressing inconsistent use of units of measure across supermarkets.

A spokesman for Coles has said the company was committed to keeping prices low at its stores.

A Woolworths spokesperson has previously said pack and serving sizes were up to the individual manufacturer.

Coles and Woolworths comprise almost 70 per cent of supermarket retail sales nationwide.

On Tuesday, the government announced an extra $30 million for the Australian Competition and Consumer Commission to help it complete more investigations and conduct enforcement.

With AAP.