For most Pakistani students the years immediately after graduation matter as much as the degree. Post-study work rights are what turn an expensive qualification into an investment that pays back, and they vary far more than applicants expect.
They also change. Several major destinations have altered their rules more than once recently, so any comparison including this one should be checked against the current official position before you commit.
What actually varies
The duration of the permission. Whether it requires a job offer or is granted openly. Whether it depends on the level of your qualification, so a master's earns more time than a bachelor's. Whether it depends on where you studied, with some countries granting longer periods outside the capital. And whether it leads anywhere, meaning whether the route connects to longer-term residence.
That last point is the one that most changes the value of a destination and the one least discussed in marketing material.
The broad shape
The United Kingdom offers a graduate route of a defined length, longer for doctoral graduates. Germany offers a job-seeking period after graduation that is generous by European standards. Australia links post-study duration to qualification level and in some cases to regional study. Canada links it to programme length and to institutional eligibility, which has narrowed. The United States offers optional practical training with an extension for eligible fields.
Each of those sentences hides conditions. Treat them as a map of what to verify, not as the answer.
Choosing with this in mind
Decide first whether you intend to return to Pakistan promptly, to work abroad for a period, or to pursue longer-term residence. Those three intentions point to genuinely different shortlists.
Then check the current rule for your intended qualification level and location, in writing, from the official source. Rules that changed after someone else's cousin went are the most common source of bad advice in this area.