What does a Facebook profile URL actually tell you?
Which of two forms it takes, and that decides whether a link you were sent last year still points anywhere.
A Facebook address is either facebook.com/ and a username the owner chose, or facebook.com/profile.php?id= and the account number Meta issued. Both appear on Meta's list of public information on Facebook. The number was issued once and cannot be edited; the username is a label sitting on top of it.
| What the link carries | What it identifies | What it is worth |
|---|---|---|
profile.php?id= and digits | The account number Meta issued | A pointer that survives every rename |
| A chosen username | A label the owner controls | A string worth running past other platforms |
Meta's rules for a custom username are narrower than people assume: letters, numbers and full stops only, at least five characters, and neither full stops nor capitals distinguish one username from another.
That last rule is the useful one. A handle copied down with the dots in the wrong places still opens the same profile.
Which fields does Meta publish whatever the settings say?
Fewer than people fear, and Meta writes the list out rather than leaving you to work it out from the menu.
| Public item | Needs a friend request? |
|---|---|
| Name, gender, username and user ID | No |
| Profile picture and cover photo | No |
| Age range, language, country | No |
| Follower count | No |
| Anything shared with a Public audience | No |
| Comments on public posts | No |
| Posts inside a Page or a public group | No |
The public information page is the source for every row. It counts each post by the audience that post carries, not by the setting the profile has today, so a photograph shared publicly in 2015 is still on it. Read the list as a floor: a stranger can see more than this, never less.
How do you trace a Facebook profile photo?
The profile picture and the cover photo are both on Meta's public list, so anybody can run them through a reverse image search.
- Open the profile picture and copy the image address.
- Run it through Google Lens or TinEye.
- Look for the earliest copy and for the same face under a different name.
- Repeat with the cover photo, which is usually a different picture from a different source.
A picture that appears earlier on another site under another name tells you the profile borrowed it. A picture with no earlier copy tells you less, because private albums are not indexed. Try a crop of the face if the full image returns nothing.
Uploads are generally re-encoded, so do not expect camera metadata inside the file. The earliest copy is the evidence.
Everything readable here was pinned up on purpose. The only question left is who the person pinning it expected to walk past.
Why did Facebook email search stop working?
Not by searching, and not since April 2018.
Meta's own announcement is the citation. Its chief technology officer wrote that people could enter another person's phone number or email address into Facebook search to find them, that malicious actors had abused the feature to scrape public profile information, and that the feature was disabled.
What survives is not a search. The setting people mean governs who Facebook can suggest your profile to based on your email address or phone number, and it offers four audiences: possible connections, friends of friends, friends, or no one. Possible connections is the default.
So Facebook is not among the 75 sources our email lookup runs. The checker written for it is switched off in our own codebase with the reason recorded beside it: the recovery endpoint answers identically whichever address you submit. Instagram arrived at the same place by a different route.
Does a phone number still find a Facebook profile?
Not as a search either, and the reason people believe otherwise has a date on it.
Meta says the file that circulated in April 2021, covering more than 530 million people, was not taken by hacking but scraped from the platform before September 2019, using software that imitated the app to upload a large set of phone numbers and see which matched. That file is still resold, and a service returning a stranger's profile from their number is usually reading a copy of it.
Our own phone module runs 9 sources and Facebook is one of them. It puts the number through the recovery flow and returns unknown, rather than no account, whenever the reply is a checkpoint or a login wall.
Read any hit as a number attached to an account, never as an identification of a person. Carriers recycle numbers, and what a number does and does not prove is its own subject.
How do you find the right profile when the name is common?
With one narrowing fact, because a name on its own is not a key and Facebook says so in writing.
Its help centre states that everyone except people you have blocked can search for you by name and open your profile, and that results respect the account's privacy settings. The companion page on a failed search gives the honest reasons: hundreds of people share a common name, or the person limited their settings, or they blocked you.
The narrowing facts that work are the ones indexed beside the name: a city, an employer, a school, a mutual friend. The mutual friend is strongest, because the search runs from your own account and ranks accordingly.
Our name module covers 15 registers and Facebook is not one. A name search returns records rather than profiles, which is a different object with different limits.
What does a Marketplace seller's profile prove?
Their rating, and on Meta's documentation that is the only field it proves.
The help centre states that seller ratings become public once five or more arrive, and that anyone who can see the Marketplace profile can see them. Buyer ratings stay private. Ratings can only be left from the iPhone or Android app, which quietly explains why a busy seller can still show none.
Everything else repeated about these profiles — a join date, a city, a count of past listings — we could not trace to a Meta page while writing this. Treat those as things a screen may show you rather than facts the platform guarantees.
The seller's ordinary profile is the better read. A cover photo and a follower count are on Meta's public list, and an account carrying neither is itself the finding.
Groups are the surface people forget is open
Because the wall is drawn around the group rather than around the member.
Meta's page on public and private groups is blunt about it. In a public group, anyone on Facebook can see who is in it. In a private group, only current members can see what is shared and who the members are.
Put that beside the public-information list and the consequence is uncomfortable. Posts and comments made inside a public group are public information, so a question asked in a local buy-and-sell group in 2019 still sits under a name, a photograph and a profile URL.
One thing we could not verify: whether membership of a group is displayed on the member's own profile. Meta's page answers the group side and says nothing about the profile side, so this post does not assert it either way.
Which Facebook lookups break the rules?
Reading a public profile is lawful. The restrictions land on what you do with it, and separately on how you collect it.
In the United States, using what you find to decide employment, housing, credit, insurance or tenancy puts you under the Fair Credit Reporting Act, and a consumer lookup service is not a consumer reporting agency. In the EU and the UK a public profile is still personal data, and processing it needs a lawful basis under the GDPR.
Collection runs on its own track. Meta says it blocks billions of suspected scraping actions a day and took more than 300 enforcement actions in a year, none of which depends on whether scraping is also an offence where you live.
Two things are out wherever you are. Anything running on somebody else's login, and using a result to contact, follow or pressure a person who has not asked to hear from you. Neither becomes acceptable because the profile was public.
Where do you start from the identifier you hold?
From whichever one you actually have, with different expectations of each.
| You hold | Go to | Facebook covered? |
|---|---|---|
| A profile URL | Read the page, then the username lookup on the username (217 platforms) | The page itself |
| A phone number | The phone lookup (9 sources) | Yes, and it answers unknown at a login wall |
| An email address | The email lookup (75 sources) | No, the endpoint answers every address the same way |
| Only a name | Find a narrowing fact first | Search runs from your own account |
Read the sources panel rather than only the hits. A source that answered and found nothing is evidence about the person, and a source that never answered is evidence about the internet.
If a name is all you hold, the narrowing fact is a city, an employer, a school or a mutual friend, and the mutual friend is the strongest.
Common questions
How do I find someone's Facebook account?
Start from a profile URL if you have one, because that is the only identifier that resolves directly. Otherwise search the name and add one narrowing fact, such as a city, an employer, a school or a mutual friend. Searching by email address or phone number stopped working in April 2018, when Meta disabled that feature.
Can you find a Facebook account by email address?
Not by searching. Meta disabled search by email address and phone number in April 2018 after the feature was used to scrape profiles. The setting that remains controls who Facebook can suggest your profile to, with four audiences and possible connections as the default. That is a friend suggestion, not a lookup anyone can run from outside.
Can you find a Facebook profile from a phone number?
Not as a live search, for the same reason. Meta says the file circulating since April 2021, covering more than 530 million people, was scraped from the platform before September 2019 by software imitating the app. Tools returning a profile from a stranger's number are usually reading a copy of that file rather than asking Facebook anything.
How do I do a reverse image search on a Facebook profile photo?
Copy the profile picture, which Meta lists as public, and run it through Google Lens or TinEye. Look for the earliest copy and for the same face under another name. A picture that appears earlier elsewhere means the profile borrowed it. No earlier copy proves little, since private albums are not indexed.
What does profile.php?id= mean in a Facebook URL?
It is the account number Meta issued, shown instead of a username. The number never changes, even when the owner renames the account or the username is edited, so a link built on it keeps pointing at the same profile. Profiles without a custom username typically show this form.
What is the difference between a Facebook username and a user ID?
The user ID is the account number Meta issued and it never changes. The username is a label the owner chose and can edit, which is why a saved link can stop working. Meta lists both as public information. Its rules allow letters, numbers and full stops, at least five characters, with full stops and capitals not distinguishing one from another.
What is always public on a Facebook profile?
Meta names the account's name, gender, username and user ID, profile picture and cover photo, plus age range, language, country and follower count. Anything shared with a Public audience is on the same list, as are comments on public posts and anything posted inside a Page or a public group. None of it needs a friend request.
Can you see who is in a Facebook group?
In a public group, yes: Meta states that anyone on Facebook can see who is in it. In a private group only current members can see what is shared and who the members are. Posts made inside a public group also count as public information, which is where people expose more than they intended to.
What can you check about a Facebook Marketplace seller?
Their rating, which Meta says becomes public once five or more arrive and is visible to anyone who can see the Marketplace profile. Buyer ratings stay private, and ratings can only be left from the mobile app. A join date or a city is not documented by Meta, so treat either as unverified rather than as a guarantee.
Can someone hide from a Facebook name search?
Not from the search itself. Facebook's help centre says everyone except people you have blocked can search for you by name and open your profile, and that results respect your privacy settings. What the settings change is how much of the profile a stranger then reads, not whether the name appears among the results.
Does Facebook tell someone that I looked at their profile?
Viewing a profile page sends no notification and Facebook publishes no visitor list. What can reach the person is what you do next: a friend request, a message, a follow or a reaction are all visible actions. Our own lookups send none of those, because they query public sources rather than the account.
Is it legal to look someone up on Facebook?
Reading a public profile is lawful in the United States, the EU and the UK. Use is what is restricted: decisions about employment, housing, credit, insurance or tenancy fall under the Fair Credit Reporting Act and cannot rest on a consumer lookup. In the EU and UK a public profile is personal data needing a lawful basis under the GDPR.
