Between 2 and 4 years for a formal education, but bear in mind that you might not be entirely hirable until you have collected a body of work that can convince an employer that you are up to the task of designing against an actual business brief. My advice: go to school. Network like crazy and take a junior design position with a small creative shop that does good work, and build your portfolio. And then when you have enough credentials behind some cool pieces, go out and look for a higher profile position.
Hi Leila B.,
The answer to your question depends on what your goals are for a career in graphic design. There are many different types of jobs for graphic designers available. One option is to pursue a 4 year degree. This would provide you with the broadest options for working in the field. The more education and experience you have, the more opportunities you will be qualified for. Another option is to pursue an an associate degree, which is 2 years, in a program that is specifically targeted and designed for a career in graphic design. Lastly, you can forgo a formal education and learn by taking separate courses, online or in classrooms. In my opinion, this would be the most difficult route, because you will need to provide your own guidance along with a great deal of determination and persistence. Your success at any of the options will depend on your current level of knowledge and skill, talent, hard work and determination. Best of luck to you, whatever you choose to pursue!