How do Australians say happy birthday?

Australians typically say "Happy Birthday" in the same way as many English-speaking countries. They might also use informal variations like "Happy B'day" or "Cheers on your birthday!" In some cases, friends and family might sing the traditional "Happy Birthday" song, often with a relaxed and cheerful vibe typical of Australian culture. Additionally, it's common for Australians to celebrate with barbecues or outdoor gatherings.