What Is a PhD?

A Doctor of Philosophy, often known as a PhD, is a terminal degree—or the highest possible academic degree you can earn in a subject. While PhD programmes (or doctorate programmes) are often structured to take between four and six years, some graduate students may take longer as they balance the responsibilities of coursework, original research, and other degree requirements with raising families or working full time. 

With a PhD, you may find opportunities to work as a university professor, a researcher in a commercial or government laboratory, a consultant, or a subject matter expert (SME). If you have intellectual curiosity and dedication, earning a PhD can be a rewarding experience. Learn more about what it takes to earn a PhD, the requirements to apply for a PhD programme, and other factors worth considering.

PhD: Key facts

Generally, students begin their PhD after earning a bachelor’s degree and a master’s degree. However, some doctoral programmes may offer you the chance to earn your master’s while pursuing your PhD, so that may not be an admissions requirement.  

What can you get a PhD in?

It’s possible to earn your PhD in a number of academic disciplines, including the natural sciences, humanities, arts, and social sciences. The following list highlights some of the subjects you can study:

• Engineering

• Biological sciences

• Social and behavioural health sciences

• Physics and astronomy

• Psychology

• Computer

• Health sciences

• Mathematics

• Agricultural sciences

• Education

• Humanities

• Business

Depending on the university you attend, you may find that the broad academic fields above break down into more specific disciplines. For example, within a biological sciences department, you might get a PhD in molecular biology or biochemistry. Within an engineering department, you might get a PhD in electrical or mechanical engineering. Philosophy, communication, history, or French might fall within a humanities department, while economics or education could fall within a social sciences department. Marketing could be a specific PhD major within a business department.

In terms of your PhD coursework and research, you will likely be expected to concentrate in some area of your larger subject. For example, a PhD in psychology may focus on cognitive science or developmental psychology, whereas a PhD in English may concentrate on British literature or world literature written in English.

Requirements to get a PhD

PhD programmes typically require at least one year of advanced coursework, as well as comprehensive exams, and the successful completion of a dissertation. Review what you do on a year-by-year basis: 

• Year 1: Take classes to develop advanced knowledge in your subject area. 

• Between years 1 and 2: Study for and successfully pass your comprehensive exams.

• Year 2: Begin working on your thesis.

• Years 4 to 6: Research, write, and defend your dissertation. 

Once you have successfully passed your comprehensive exams, you’re typically considered “All But Dissertation” or ABD, which signals that you’ve finished everything in your doctoral programme except your dissertation. 

Research supervisor 

PhD students often choose a faculty member who specialises in their area of interest to serve as the research supervisor. It can help to identify professors or programmes that will support your research endeavours before applying, so you can establish a relationship with your potential research advisor early. 

PhD costs 

The average cost of a PhD programme in Canada is around $7,700 CAD annually, though that figure can differ based on the type of institution you attend and what you study [1].

Reasons to get a PhD

Earning your PhD can be an immensely rewarding experience, but the degree can be a big commitment, requiring significant time, money, and work. 

Here are some more reasons you may want to pursue a PhD:

• Become a subject matter expert in a particular field.

• Conduct the research you are passionate about.

• Develop transferable skills that can help in your professional life. 

• Make a difference in the world with new research.

• Make connections with scholars in your academic community.

• Open up career avenues in academic and research work.

Completing a PhD can reveal to employers that you possess a wide range of competencies that are valued in both academic and non-academic settings. 

PhD salaries

PhD holders earn an average income of $97,581 CAD per year, though that figure can differ based on what you study [2].

Requirements to apply to a PhD programme

PhD programmes expect you to meet several requirements before enrolling. Here are some examples of common requirements:

• Have a master's degree or a bachelor's degree with an additional year of study at the graduate level

• Take the Graduate Record Examination (GRE) or Graduate Management Admission Test (GMAT) and achieve a minimum score.

• Submit a proposal describing the questions you want to research

• Submit your CV.

• Provide letters of recommendation, which should ideally come from academic faculty members who can speak to your research or intellectual abilities.

Requirements differ by programme and school, so take time to become familiar with the entry requirements of universities to which you’re interested in applying. Admissions staff or departmental staff should be able to give you specific information about their admissions requirements.

If a programme is interested in you, based on your application, you may have to complete an interview. The university representatives that interview you will look at your motivation, how prepared you are, and how suitable you are for acceptance into the doctoral degree programme.

PhD vs other terminal degrees

Terminal degrees are the highest degree available in a field of study. While a PhD is the highest academic degree you can earn in a field of study, a Juris Doctor (JD) is the highest degree you can earn in law, and a professional degree, such as a Doctor of Medicine (MD) or a Doctor of Veterinary Medicine (DVM), is the highest degree you can earn in these medical professions. 

Professional doctorates are a different category of doctorate degrees. They are usually intended for professionals already working in a field who want to pursue advanced training in their area. The main difference between a professional doctorate and an academic doctorate has to do with subject matter and research. While PhDs are interested in conducting new research, professional degree students take existing models and knowledge and apply them to solve problems. Professional doctorates are also designed to prepare learners for careers in a certain industry rather than academia.  

Examples of professional doctorates include:

• DBA (Doctor of Business Administration)

• DNP (Doctor of Nursing)

• EdD (Doctor of Education)

• DPH (Doctor of Public Health)

Is someone with a PhD a doctor?

You can use the salutation "Dr" to address people who hold doctorates, including PhDs and other professional degrees. The word "doctor" comes from the Latin word for "teacher," and PhDs are often professors at universities. While it has become more common to refer to medical doctors as “Dr”, some professors use the honourific when addressing students and in professional settings.

Explore career and education options with Coursera

PhDs are advanced degrees that students can earn after receiving their undergraduate and sometimes master’s degrees. PhDs often include years of classwork and a research-based thesis and dissertation. Learning online can be a great way to explore a field you're interested in, discover career paths, and even decide whether a PhD is for you. Consider the Professional Certificates on Coursera, available from Google, Meta, IBM, Salesforce, and other industry leaders, and gain job-ready skills that employers are looking for.

Ready to get a Master's degree? Coursera partners with universities to offer online Master's degrees in a range of fields like data science, public health, and business.