About half of Australia's workers will probably be looking for a new job in the next year because they're disengaged.

The Snapshot of Australian Workplaces, commissioned by global think-tank Reventure Ltd, found that disengagement was driving 49 per cent of those surveyed to eye off a new job.

The top reasons: employees were unhappy with leadership, didn't feel like their job was meaningful or it didn't utilise their strengths.