Every site owner eventually runs into the same question: which version of the address should be the main one? With www or without it, with a slash at the end or without, on http or on https? That affects not just how your links look, but also how search engines index pages, whether they pass authority correctly, and whether that authority gets split across duplicates.
In this article, I will break down each variation, show the difference with examples, and give you simple rules for choosing one consistent URL format.
In Simple Terms: Why a Site Can Exist in Four Versions
Imagine your site has several identical doors leading into the same room:
- One door is called
site.com, another iswww.site.com, a third issite.com/, and the fourth ishttps://site.com.
Users and search engines can come in through any of them, but the room is still the same. If you do not close the extra doors, authority gets spread out and duplicates show up in search results.
Your job is to keep one main door and redirect the others to it with a 301 redirect. That keeps rankings intact and avoids confusing visitors.
www or non-www: which one should you choose?
The www version (for example, www.example.com) and the non-www version (example.com) can technically point to the same site, but search engines treat them as different addresses unless redirects are set up.
In the past, www was added to show that it was a web server, unlike ftp.example.com or mail.example.com. Today it is mostly a tradition. Most modern projects choose non-www because it is shorter and easier to remember.
Examples of non-www:
https://poznayu.com— the site’s main address withoutwww.https://yandex.com— the search engine uses a non-www version.
Examples of www:
https://www.google.com— Google uses the www version.https://www.facebook.com— Facebook does too.
What should you choose? If you are starting a new project, go with non-www. If you already have links pointing to the www version, just set up a 301 redirect from www to non-www, or the other way around.
The important thing is to be consistent.
Trailing slash — with or without it?
A trailing slash is the slash at the end of a URL, like site.com/catalog/ versus site.com/catalog. From a file-system perspective, the slash can mean a directory, while no slash can mean a file.
For a web server, those are different requests. If the same content is available under both versions, search engines see duplicates again.
Examples with a trailing slash:
https://poznayu.com/page/— a section page with a slashhttps://en.wikipedia.org/wiki/URL/— Wikipedia often uses a slash.
Examples without a trailing slash:
https://habr.com/post/12345— Habr articles without a slash.
General rule: for the homepage (site.com), you do not need a slash — that is the root. For nested folders and sections, it is better to pick one standard.
If you have a static site with real files (index.html), then site.com/page and site.com/page/ may point to different files or to the same one. Modern CMS platforms like WordPress and Joomla usually add the slash to category URLs and remove it for posts.
Pick one scheme and redirect the other version to the main one.
http → https: security comes first
The https protocol is the secure version of http, and it encrypts the data between the browser and the server. Since 2014, Google has officially used HTTPS as a ranking signal. Without HTTPS, browsers show a “Not secure” warning, which scares visitors away.
That is why today every site should run on HTTPS, and the HTTP version should be redirected to HTTPS with a 301 redirect.
Correct http → https examples:
http://poznayu.com→https://poznayu.com(redirected via.htaccess).http://www.poznayu.com→https://www.poznayu.com(if you had chosen www).
Wrong examples (what not to do):
- Leaving HTTP accessible without a redirect — users will see a warning about an insecure connection.
- Having both HTTP and HTTPS versions live without redirects — duplicate content.
To move to HTTPS, you need an SSL certificate, for example a free one from Let’s Encrypt, and you need to configure the server. After that, make sure all internal links point to HTTPS, and update the address in Google Search Console.
Comparison table of URL options
Below is a table that will help you quickly understand which combinations exist and how to handle them properly.
| Source URL | Problem | Correct solution |
|---|---|---|
http://site.com |
Insecure protocol | 301 → https://site.com |
http://www.site.com |
www + insecure | 301 → https://site.com (or https://www.site.com) |
https://site.com |
Main version (if you chose non-www) | Leave it as is, redirect the other versions here |
https://www.site.com |
Main version (if you chose www) | Leave it as is, redirect the rest |
https://site.com/ |
Extra slash on the homepage | 301 → https://site.com |
https://site.com/page/ |
A page with a slash, if you chose no slash | 301 → https://site.com/page |
How do you choose one version? A step-by-step method:
- Decide whether you want www or not. I recommend non-www because it is shorter and more modern. If you have an older project with many external links pointing to www, keep www.
- Choose your slash policy. For the homepage, a slash is not needed. For internal pages, follow your CMS standard. For example, WordPress adds a slash to categories but not to posts. That is normal. The main thing is that one URL should not have two versions.
- Make sure HTTPS is enabled. That is non-negotiable. SSL certificates are free, and the SEO and trust benefits are obvious.
- Set up 301 redirects from the non-canonical versions to the main one. In Apache (
.htaccess), this is done withRedirectorRewriteRule; in Nginx, usereturn 301. - Check your redirects with webmaster tools or online services. Make sure there are no chains, such as
http → https → www → non-www.
If you go deeper into SEO, from Google’s point of view these options are not inherently better or worse: the search engine chooses a canonical version from the duplicate set and treats the others as alternate URLs.
So the job is not to argue with search engines, but to clearly define one main version with a permanent redirect and, when needed, rel="canonical".
| Method | How search engines see it | Pros | Cons | Practical takeaway |
|---|---|---|---|---|
| www / non-www | These are different URLs; Google does not have to treat them as one unless you combine them yourself. | You can choose one main domain and consolidate signals into one version. | If both versions are live, you get duplicates and signal dilution. | Pick one main version and 301 the other one to it. |
| trailing slash / no slash | Google has historically treated URLs with and without a slash as different addresses, even though the user sees almost no difference. | Lets you standardize URL structure strictly. | Without a standard, it is easy to end up with two versions of the same page. | Pick one format and apply it to all internal links and redirects. |
| http → https | Google treats this as a site migration; HTTPS is the standard for a secure web, and the move should be done with redirects. | Security, trust, and one consistent site version. | If both versions stay live, you get duplicates and canonical confusion. | Do the move with a 301, and fully transfer the old HTTP version to HTTPS. |
In short, search engines do not “punish” you just for using www, non-www, or a slash, but they do rank and display the canonical version if you set it correctly. If you do not set it, Google will choose the canonical version itself, and that may not be the URL you actually want.
- If you want one working setup without extra hassle, the usual approach is this:
https://www.orhttps://without www, but always one standard across the entire site, with 301 redirects and matching internal links. - What matters to Google is not which version you choose, but that there is only one and that it is used everywhere.
Examples for a .htaccess file to redirect from www to non-www and from http to https:
RewriteEngine On
RewriteCond %{HTTPS} off [OR]
RewriteCond %{HTTP_HOST} ^www\. [NC]
RewriteRule ^(.*)$ https://poznayu.com/$1 [R=301,L]Final result: examples of correctly chosen URLs
For the site poznayu.com (non-www, no slash, https), the correct main version is https://poznayu.com.
All other versions:
http://poznayu.com→ 301 tohttps://poznayu.comhttp://www.poznayu.com→ 301 tohttps://poznayu.comhttps://www.poznayu.com→ 301 tohttps://poznayu.comhttps://poznayu.com/→ 301 tohttps://poznayu.com(remove the slash)
For an internal page: https://poznayu.com/page. If someone lands on https://poznayu.com/page/, there should be a redirect to the version without the slash.
Remember the main point: one consistent URL is not just about SEO, but also about usability. Users should not have to guess how to type the address, and search engines should not have to merge duplicates. Spend one hour setting up redirects, and your site will thank you.
I’m Ethan Carter, an American developer and technical writer with more than 20 years of experience in systems and application programming. My core specialty is low-level development in Assembler: 22 years of hands-on work, including deep experience in code optimization, CPU architecture, and performance-critical solutions. I also hold a PhD in Assembler and have spent more than 18 years working with ASP.NET, building enterprise web systems, APIs, and scalable backend solutions.
In addition, I have 9 years of experience in C++ and C#, along with 7 years of hands-on microcontroller programming in Assembler. Thanks to this mix of academic background and practical engineering experience, I can write about software architecture, low-level optimization, and modern development in a way that makes complex technical topics clear for a professional audience.
