What does a stranger know about you?

A curious stranger may be able to create a surprisingly detailed picture of your life

YOU’VE PROBABLY NEVER even seen them. You’ve never talked to them. But if you were to give a curious stranger 20 or 30 minutes, a laptop, and a few simple details about you, they may be able to create a surprisingly detailed picture of your life.

Think of a typical London business owner or professional. Start with a name. Add a LinkedIn profile, an Instagram account, an old Facebook post, a company bio, a photo from a charity event, and perhaps an old username from years ago.

At this point, a stranger may know where you work, what you do, which neighbourhood you typically spend time in, where you attended school, who some of your relatives are, and when you tend to travel.

“People are often most surprised by how much they have unknowingly made available about themselves,” says Michael Porter, senior private investigator with Haywood Hunt & Associates Inc. “Information by itself can seem relatively insignificant. When you combine 10 separate pieces of information, however, you begin to see a much larger picture.”

This larger picture is known as your digital footprint, and Canadians are becoming increasingly concerned about who can view it.

According to the Office of the Privacy Commissioner of Canada’s 2024-25 survey, 92% of respondents indicated that they had concerns about the sale or sharing of their personal data with third parties. Only 12% said they trusted social media companies to safeguard their personal information.

There Is Likely More Than You Realize That Identifies You

Much of what makes you easily searchable can seem completely harmless when you post it.

A birthday post could reveal your birth date.

An announcement about your “new job” could identify your employer and approximate start date.

A congratulatory comment from Mom could identify a family member.

Photos of your dog could reveal a pet name that you may have used elsewhere as the answer to a security question.

Real-time vacation photos may alert others that you are currently away from home. Canada’s Privacy Commissioner specifically cautions people about revealing location information through social media while travelling.

Images can also reveal more than initially meets the eye. Image file metadata may contain the date and time a photo was taken. Depending on the device and its settings, geographic location information may also be embedded.

Porter notes that researching someone often involves piecing together many individual details to develop a fuller understanding of that person’s identity, activities, or behaviour patterns.

“It is always a puzzle,” he says. “Here is a name. Here is a workplace. An old social media account. A public record. A photo. A comment from someone else. You validate each element and determine whether it actually connects.”

You also do not control every piece of information about yourself that appears online.

Your own accounts may be private, but your local softball team may have published a roster. Your employer may list staff members on its website. A family member may have tagged you in a photograph. Your name may appear in an old news article, professional association directory, corporate record, charitable fundraiser, or community event.

Removing something after it has been posted may not completely solve the problem. Online content can be copied, shared, saved, or cached before it is deleted. The Office of the Privacy Commissioner of Canada has warned that photos, comments, and other information posted online can be difficult to completely remove.

Turning Innocent Information Into Convincing Scams

For anyone whose name appears on a company website, there is also a business risk to consider.

The Canadian Centre for Cyber Security advises that criminals behind targeted spear-phishing attacks may gather publicly available information about their victims from social media profiles, company websites, and online activity before making contact. Those extra details can make a fraudulent message seem much more credible.

For example, consider the following email:

“Hello Mike,

I’m aware that you’re attending the conference in Vancouver this week. Can you please take care of this invoice before the afternoon session?”

That sounds far more convincing than an email beginning with “Dear Sir.”

The scammer may never have met Mike. The conference details could have come directly from his LinkedIn post.

Publicly available information is increasingly useful for this type of social engineering. The Canadian Centre for Cyber Security notes that threat actors frequently use information collected from public sources, including social media, to make their communications more believable.

The financial losses can be substantial. During the first six months of 2026, Canadians reported approximately $351 million in fraud losses to the Canadian Anti-Fraud Centre. Spear phishing was among the types of fraud showing notable activity compared with 2025. The CAFC estimates that only 5% to 10% of fraud is reported.

Conduct an Experiment on Yourself

How exposed are you?

Try a five-minute test.

Search your full name in quotation marks. Search your name along with your employer, city, and profession. Browse through the image results. Search any old usernames you still use. View your LinkedIn profile while logged out.

Next, pretend you know nothing about yourself.

What could someone correctly figure out?

Could they identify your spouse from anniversary photos? Your favourite restaurant from repeated tags? Your running route from fitness posts? Your vacation plans from a countdown post? Your company’s senior management team from LinkedIn? The software your business uses from a job posting?

Porter recommends thinking about how separate pieces of information work together.

“You can maintain a professional presence online without documenting every detail of your life,” he says. “Before posting something, think about what it tells somebody who has no other context about you. Then think about what it tells them when it is combined with everything else that is already public.”

Businesses can benefit from the same exercise. Staff profiles, social media accounts, job listings, photographs, and company announcements can collectively reveal organizational structures, travel schedules, vendors, technology platforms, and key decision-makers.

There is an interesting paradox to modern internet use. We spend a great deal of time worrying about sophisticated hackers breaking through digital barriers. Sometimes the easiest information to obtain is already sitting outside the wall, waiting to be collected.

The stranger looking you up may be a potential employer, customer, salesperson, scammer, private investigator, or simply someone who is curious.

Perhaps the better question is no longer, “What have I posted online?”

It may be: “What story could a stranger build from it?”