Clarke was speaking as Australia's players get set to enjoy a six-week lull before some heavy-duty fitness work, followed by three one-day games against Bangladesh in Darwin next month. Australia will then visit No. 2-ranked India for four matches in October and November.
The domestic line-up includes three Tests each against seventh-ranked New Zealand and fourth-rated South Africa, with a return series away to the latter early next year, followed by the Twenty20 World Cup in England in June and an Ashes series against world No. 3 England.
"It's going to be a huge 15 months," The Age quoted Clarke as saying at Sydney Airport yesterday.
"We have some really tough cricket in both forms of the game coming up, so we're going to find out where we sit in both forms," he added.
Australia faces an equally daunting schedule of limited overs assignments with games against its closest rivals South Africa and New Zealand.