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Study a PhD: A Guide to PhD Degrees

Looking to undertake PhD studies? This guide will tell you everything you need to know about PhD studies.

Jul 24, 2023
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What is a PhD/Doctorate degree?

A Doctor of Philosophy, more commonly known as a PhD, is the highest level of degree you can achieve in one field of study. It’s awarded by universities around the world for significant contributions to knowledge in various academic fields, or upon completing a PhD program.  

Pursuing a PhD involves conducting in-depth original research in a certain field. The results of this research are then compiled into a thesis or dissertation. This usually culminates in an oral examination or defense, where the candidate must demonstrate comprehensive knowledge of their research area and defend their findings in front of a panel of academics in that subject field. 

Different Types of PhDs

“PhD” is an umbrella term for different types of programs. These can be broadly divided into four categories:  

  1. Traditional/Academic PhDs: Also known as a research doctorate, this involves a couple of years of original research on a specific topic. It usually focuses on a theoretical understanding of the topics, rather than practicing the knowledge in the professional setting. This is the most common type of PhD. 
  2. Professional Doctorate: These are designed for professionals who want to apply their research to their professional practice. Examples include the Doctor of Education (EdD), Doctor of Psychology (PsyD), and Doctor of Business Administration (DBA). These degrees are often more practice-oriented compared to the traditional PhD. 
  3. Higher Doctorates: These are awarded to people who contributed greatly to the research and knowledge body within their field and are thus given out later in that researcher’s life. You can’t apply for this type of doctorate like a regular PhD program. 
  4. Honorary Doctorates: These are given out by universities at their discretion, and don’t require any specific academic achievement or publication. Just like Higher Doctorates, you can’t apply for this type of Doctorate. 

What the breakdown above suggests is that you essentially have two options when it comes to pursuing a PhD – you can either opt for an academic route, or a professional/industry doctorate

Studying for a PhD

How Long Does It Take To Get a PhD?

On average, PhD programs last 5-7 years, but this number varies greatly depending on the country, the university, and the specific field of study.

For example:

  • PhD programs in the UK tend to be on the shorter end of the spectrum, typically lasting 3-4 years.
  • In the US, however, the average completion time for PhDs rounds out at 6 years.

Make sure to keep in mind that the time it takes to earn a PhD also depends on the pace of your study, the field of study, the requirements of your program, and your prior educational background.

What Are The Requirements To Study A PhD?

You’ll need to do some preparation in order to successfully apply for a PhD. The general rule-of-thumb is to check the university’s website for the specific requirements of the program you’re interested in. 

That said, there are some general requirements you’ll need to meet to pursue a PhD: 

Academic Transcripts  

You’ll be expected to submit transcripts of your Bachelor’s and Master’s studies, which have to show the courses you took and grades you received during your programs. 

Some PhD programs in the UK, particularly in STEM fields, may allow you apply for a PhD with only a Bachelor’s degree. However, PhD programs in Arts and Humanities require a Master’s degree. 

You may need to have to get your transcripts (and other documents) translated and stamped by a notary. For example, if you got your Bachelor’s and Master’s in Hungarian, but you’d like to study in Canada, you will need to get your transcripts translated into English. 

Research Proposal 

The majority of universities require students to submit a research proposal as a part of their PhD program application, unless if you’re applying for a pre-defined research project in science, technology, engineering, mathematics or medicine. Make sure if this exception applies to your program of interest. 

A good research proposal includes the scope, significance and some details about the topic you plan on researching during your program. 

Your research proposal will have varying significance depending on the country you’re planning on studying in. 

Academic CV/Resume 

The general practice is to include your education at the top of the CV, followed by work experience and then academic research. 

Make sure to check the industry standard for CVs/Resumes in the country and field you want to study in. For example, U.S. Resume may differ from your home country’s standards – it will make you stand out above other candidates who didn’t take that time to research your study destination’s standards. 

Note: While not adhering to the CV/Resume standards of the country/university won't immediately disqualify you as a candidate, it does show a certain lack of care and polish that other candidates might showcase in their own applications. The best way to describe is that details like this show your determination and proactiveness (because you're actively thinking about what could leave a better impression on the admission committee).


Motivation Letter/Statement of Purpose 

Research the university and the faculty thoroughly 

To compose an effective motivation letter for your PhD application, it’s crucial to thoroughly research the university and the faculty you're interested in. This is something recruiters and admission committees are actively looking out for - they want to see that:

  • You know what the university/faculty is about
  • You're familiar with the projects the department you're interested in is involved in
  • You care enough to learn about the professors, researchers, and other people at the department you're applying for

It's not only about looking good - this thorough approach shows dedication and leaves a positive first impression when it comes to your research skills and maturity.

Avoid clichés and communicate who you are

Faculty members and admission committees have likely sifted through countless formulaic letters and readily available templates from the internet, so your authenticity and genuine enthusiasm will set you apart.  

Remember that no one expects you to be perfect - admission committees hire on potential, not perfection. Craft an interesting narrative unique to you, and articulate why that specific university and its PhD program align with your research interests and career aspirations. Don't forget to also explain why you are the right choice for them

Bonus tip: If you have been involved in the process of securing funding for research in the past, make sure to mention that. This is especially important for institutions that don’t have internal funding, but it’s always a bonus no matter where you apply. 

Letters of Recommendation and/or References 

Some universities and programs require you to submit letters of recommendation and academic references from people who you’ve studied under or collaborated with in the past. 

Make sure to give people you want recommendation letters from enough time to write a strong letter detailing why you’re the right choice for this.  

Proof of Language Proficiency 

You’ll need to prove that you can speak and write in the language you want to study in. This usually means taking a language proficiency test.  

Here are some examples of certificates that are widely accepted for different languages: 


* General German language test for all foreign higher education students.
** German language test for those who want to study at Vienna University. Lots of universities in German-speaking countries offer their own specialized German courses like this, and they're often free or very affordable.

Additional Requirements 

If you're non-EU/EEA/Swiss citizen, you may be required to apply for an Academic Technology Approval Scheme (ATAS) certificate if you want to get a PhD in certain subjects in the UK. You can check if you need to apply for this clearance on the UK government website

You may need to complete graduate entry tests to apply for a PhD in certain countries – most commonly in the US, Canada, Australia and India. These include but are not limited to:

University professor

What Are the Benefits of Getting a PhD?

A PhD can equip you with a variety of skills and a deep knowledge of your chosen field, but it also offers tangible benefits.  

Laura Forsberg White, PhD and a Professor in Biostatistics at Boston University, in the KAS interview with her, listed the following as the key skills students acquire in graduate programs: 

Hard Skills and a Deep Understanding of Your Field 

A PhD allows you to delve deeply into your field of interest, exploring complex theories, methodologies, and concepts in a profound way. You will gain hard skills that can be applied in a variety of contexts within your area of specialization. This level of knowledge makes you a sought-after professional in academia, industry, or the public sector. 

The example Prof. White gave was in her own field: students in Biostatistics and adjacent fields learn practical knowledge and skills in statistics, probability, critical analysis and more. 

Research Skills and Collaboration 

An essential part of many PhD programs is based around developing research plans, performing data collection and analysis, and presenting your findings. This cultivates strong research skills that are highly valuable both in academia and industry, in sectors such as finance, tech, consulting, and more, where data-driven decision-making is crucial. 

What’s more, PhD programs involve lots of collaboration with other researchers, which matures you as an individual and teaches you various soft skills you’ll need to succeed in your future roles, such as proper communication, taking and receiving feedback, critical thinking, time management and resilience and perseverance

Transferrable Skills 

Aside from academic knowledge and research skills, a PhD program helps you develop a range of transferable skills. These include project management, leadership, team working, and communication skills. Such skills are highly valuable in a variety of professional contexts. 

Many PhD programs also require students to undertake teaching or mentoring roles. This offers valuable experience if you aim to pursue a career in academia, giving you the chance to shape the minds of future generations and contribute to the growth and development of your field of study. 

Career Advancement 

If you decide to leave academia to pursue a career in the industry, a PhD can open up higher-level career opportunities, such as more prestigious roles, higher pay, and quicker promotions.

It's also worth noting that a PhD is often required for tenure-track positions in academia.

What’s more, during your PhD, you'll attend conferences, seminars, and other academic events. These platforms allow you to meet and collaborate with other professionals, academics, and experts in your field. Such networking can lead to fruitful collaborations, job offers, or research partnerships

Contribution to Society 

As a PhD researcher, your work could lead to significant breakthroughs or advancements in your field. Whether you're studying medical sciences to contribute to public health, or researching environmental science to advance sustainability efforts, your research can make a real difference in society and/or the overall body of knowledge of your chosen field. 

Man working

What Is The Average Salary of a PhD Graduate?

When we consider pursuing higher education, one of the key factors that often drives our decisions is the potential impact it will have on our financial future. A PhD can provide the edge you need to not only secure high-paying roles but also garner respect and credibility in your chosen field

The average salary of PhD graduates varies significantly across countries and fields: 

United States

  • Bachelor’s degree average: $70,000/year
  • Master’s degree average: $82,000/year
Job TitleAverage Salary (PhD)
Mechanical Engineer$113,108
Data Scientist$112,397
Research Scientist$95,747
University Professor$94,068
Clinical Psychologist$88,910

Source: Payscale, 2023

United Kingdom

  • Bachelor’s degree average: £33,000/year
  • Master’s degree average: £35,000/year
Job TitleAverage Salary (PhD)
Senior Software Engineer£67,062
Quantitative Analyst£57,886
Senior Research Analyst£43,539
Senior Lecturer£54,967

Source: Payscale, 2023


  • Bachelor’s degree average: €51,000/year
  • Master’s degree average: €56,000/year
Job TitleAverage Salary (PhD)
Senior Software Engineer€70,005
Risk Manager€61,042
Research & Development Engineer€59,321
University Professor€80,000
Senior Environmental Professor€66,330

Source: Payscale, 2023

How Much Does Getting a PhD Cost?

A PhD can cost you nothing or a fortune, depending on the university and the country in which you want to study in. Most universities also have different tuition fee structures for domestic and international students.  

Here’s a breakdown of the average tuition fees depending on the region and citizenship:  

CountryAverage cost
United StatesPublic institutions: Usually $10,000- $12,000 for in-state students and double or triple that for international students.Private institutions: Usually $20,000- $30,000 for in-state students. International student fees are usually higher.
United KingdomAnywhere between £4,500 (for domestic students) to over £30,000 per year (international students).
GermanyNo tuition for the first six semesters of your PhD studies. After that, you’ll need to pay €300 per semester.
SwedenFree for all students regardless of their country of origin.
FranceNo tuition fees, but there is an administrative cost of €380 per year.

You can read a more detailed breakdown of the costs of getting a degree in various countries in our Country Guides.

For those of you worried about the costs of studying abroad, there are plenty of scholarships out there to help you find your studies. Take a look at our free Scholarship Directory for a list of 440+ scholarships in 37 countries around the world.

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Can I Do a PhD Online?

Yes, you can definitely complete PhD programs online. More and more of them are available every year, but it's important to remember that their quality varies widely depending on the field of study and the institution.

It would be good to check how long the online program you’re interested in has existed. PhD programs are collaborative by nature, and many majors aren’t a good fit for online studies.

Typically, PhD programs specifically designed for online instruction tend to be more effective compared to traditional programs that have been simply transferred to online learning platforms.

Need More Help With Your PhD Application?

Download our free PhD Application Documents handbook, which goes into detail on how to perfect your motivation letter, CV/resume, research proposal and more!