Visitor visas (subclass 600) typically take around 10-15 days to process. During peak seasons like December to February, it may take 3-4 weeks.
Work and Holiday visas (subclass 462) can take up to 8 weeks. The earlier you apply the better.
Student visas (subclass 500) usually take 4 to 6 weeks to finalize but can take 2-3 months during peak periods. Plan ahead!