Are cold emails useful? In my opinion, if your resume is strong, a good cold email can definitely be beneficial.

So, what makes a good cold email?

First, you need to clearly understand the primary research focus of the advisor’s lab. For example, my lab is mainly doing NLP-related research, but I often receive emails from students expressing interest in “general AI applications”, “general machine learning”, or even areas like “pure computer vision” or “3D”. Such broad, vague, or misaligned research interests can make your email seem “templated”, and this may negatively affect the advisor’s impression of you. If you are trying to switch research fields, especially to one that differs from your prior experience, it’s important to explain why.

Next, highlight what makes you stand out. This could be your publication record, industry experience, or even a unique side project.

Finally, and what I believe is most important, take time to read the lab’s papers. Share your thoughts on specific papers, discuss topics that could be extended into new projects, and ideally connect them to your previous research experience. This is a great opportunity to demonstrate your research taste - whether the papers you select are those the advisor values. It also demonstrates your independent thinking ability - if your past research experience allows you to form your own thoughts on a new topic. Of course, simply writing “I read your paper on XXX and found it very interesting” isn’t enough. You need to provide concrete insights.

In short, a good cold email should demonstrate your passion for research, what makes you unique, whether you can think independently, and if you are willing to invest time into topics you might work on. These are all crucial indicators of a strong PhD candidate. For me, if an email looks like it could have been sent to multiple advisors without any changes, it’s very likely to be ignored.

Lastly, there are many reasons you might not receive a reply to your cold email. It could be that your resume does not meet the requirements, your email is too general, you do not highlight anything special, or it could simply be that some advisors prefer not to respond.