It is hosted by former newsreader Richard Morecroft, co-hosted by David Astle and Lily Serna.

Although it is based on the French game show Des chiffres et des lettres, its structure is similar to the UK version of the show, Countdown - with the titular difference being used to avoid confusion with the Australian music program Countdown.

On 5 July 2021, SBS announced that Letters and Numbers would be revived in a new series hosted by comedian, journalist and actor Michael Hing.

[3] On 3 September 2021, it was revealed that the revival would be a celebrity version of the show, entitled Celebrity Letters and Numbers, and that David Astle and Lily Serna would return to co-host the series which premiered on 2 October 2021.

After the first commercial break, Astle would present a story on the origins of particular words and phrases.

Retired champions with the highest cumulative score may return for a special tournament at the end of each series.

One contestant chooses how many vowels and consonants they would like to make up nine randomly chosen letters.

The contestants then have thirty seconds to find the longest word that they can make out of these letters.

If neither contestant buzzes in with a correct answer during the time limit then no points are awarded.

Before the commercial break, the audience is given a "Word Mix"—an 8-letter anagram similar to the conundrum, but accompanied by a verbal clue.

Fisher and Fernando from Series 1 have also been rivals outside of Letters and Numbers since the 1990s, having been involved in other mind-puzzle games at tournament level, most notably the Channel News Asia Scrabble Masters tournament held in Singapore in 1999.