There are two streams for the Subclass 485 visa:
For students who have completed at least 2 years of study in Australia, and who nominate an occupation on the Australian Skilled Occupation List. The study undertaken must be closely related to the nominated occupation. Subclass 485 visas granted under the Graduate work stream are valid for 18 months
This stream allows international students who have completed a bachelor's degree or higher at an Australian higher education institution to remain in Australia for up to 4 years. Applicants for this stream do not need to nominate an occupation on the Skilled Occupation List (SOL). Subclass 485 visas granted under the Post-study work stream are valid for between 18 months and 4 years, depending on the applicant's qualifications:
Bachelor's degree or taught master's degree - 2 years
Research based master's degree - 3 years
PhD - 4 years
Unlike most General Skilled Migration visas, applications are not by invitation only, and applicants do not need to submit an Expression of Interest for this visa. However, there are some conditions applicants must meet in order to apply.
Applicants must:
Be older than 18 and less than 50 years of age when they apply
Meet general Skilled Migration basic requirements, including English language, health, and character checks
Meet the 2-year study requirement