Australia's population is set to hit 23 million by early May.

According to the Australian Bureau of Statistics' (ABS) online population clock, the nation had 22,919,956 residents as at 10am (AEDT) Friday.

The overall population increases at a rate of one person every one minute and 24 seconds, the ABS estimates.

ABS demographer Guy Jennings told AAP the population clock was a "simplified projection", but on current estimates the 23 million mark could be hit in early May.

The clock will updated on March 28, which could result in a later or earlier date for the milestone to be reached - depending on the birth and death rate and migration intake.

Mr Jennings said it wasn't accurate enough to pick a specific date.

But AAP's back-of-the-envelope calculation suggests the 23 million-mark could be reached on May 7.

The 22 million mark was hit in September 2009.