If you’ve read many of our other posts here, you know that we are strong advocates for a good SEO strategy. URL design is one of the most underrated search engine optimization techniques, yet it carries a lot of weight on your overall SEO strategy. As a rule of thumb, your URLs need to be short, keyword-rich, and descriptive enough for users.
After many years of developing SEO content for our clients, it’s our contention that the URL is woefully under-appreciated as the most fundamentally important technology of the web, more important than HTTP, and even more important than HTML.
The purpose of this post is to provide a solid background on the importance of good URL design from a perspective most website owners can appreciate; search engine rankings!
URL Design for SEO: The Concept
For those unfamiliar with Google’s core algorithm for determining its search engine results, you can read this article to learn about PageRank in more painstaking detail. Here, I’ll just try to explain the aspects of PageRank as it relates to URLs. Note also that my explanations are simply meant to be a conceptual guide and not exacting details.
The founders of Google did publish their initial algorithms but have since made tweaks that are as closely-held a corporate secret as the formula for Classic Coke!
Popularity is the Key
PageRank is essentially a popularity rating, and a page’s PageRank is determined by the inbound links from other pages on the web. A PageRank can be as low of almost zero (0) to as high as ten (10).
Google’s algorithms determine a page’s PageRank by dividing the PageRank for each of the inbound linking pages by the number of outbound links on each of those pages, factoring in each page’s PageRank, and then summing the results for all inbound links. Clear as mud, right? It’s easier to explain with an example, but let’s cover a bit more ground first.
Like voting company shares
PageRank considers each link a ‘vote’ for the page linked to. But unlike in a democratic “one citizen, one vote” society, Google’s algorithm more closely models the shareholders of a corporation voting their shares; the votes of those with “more” (PageRank or shares) have a greater influence on the outcome.
So a link from a page with a PageRank of 7 is more valuable than a link from a page of PageRank 3; probably many orders of magnitude more valuable, as you’ll see next.
The old 80/20 rule, on steroids
Because of the nature of the web, a small number of pages have a huge number of inbound links, and vice versa. So those with more links get more PageRank, but the value of PageRank is on a logarithmic scale, thus it increases exponentially. Assuming that the base was five (5), the value a page would get to vote based on its PageRank and would look like this:
| PageRank | Value |
| 0 | 0 |
| 1 | 5 |
| 2 | 25 |
| 3 | 125 |
| 4 | 625 |
| 5 | 3,125 |
| 6 | 15,625 |
| 7 | 78,125 |
| 8 | 390,625 |
| 9 | 1,953,125 |
| 10 | 9,765,625 |
An example:
Assume a website somehow manages to get a persistent link from LinkedIn. Let’s assume LinkedIn’s page contains about 70 outbound links and has a PageRank of seven (7). Let’s also assume that there are a total of 50 other inbound links, and let’s say the average PageRank for those pages linking in is three (3) and those pages have an average outbound link count of 10.
From this, let’s calculate the PageRank:
LinkedIn’s Available PageRank per outbound link:
78,125 / 70 => 1,116
PageRank value contributed by 50 other sites:
125 * 50 / 10 => 625
Total PageRank value:
1,116 + 625 => 1,741
Looking it up in the table, the resultant PageRank for the home page is four (4).
The Three ‘P’s of Inbound Links
As with the three ‘L’s of real estate, the three ‘P’s of inbound links are PageRank, PageRank, PageRank! Note how in the prior example the 50 inbound links of PR3 offered less PageRank than the one (1) inbound link from LinkedIn with PR7! Of course we don’t know the logarithmic base but Phil Craven says 5 or 6.
So depending on the logarithmic base, PageRank fluctuates between four (4) and five (5) for this hypothetical example. However, starting with a logarithmic base of five (5) the one LinkedIn link overpowers the 50 others!
And because pages with a PageRank closer to 10 are listed higher in Google’s search engine results page among competing pages, people focused on SEO are always trying to increase their page’s PageRank, often via unscrupulous means: Black Hat SEO
Of course nobody outside Google knows the exact formula or base exponents used, but hopefully, this post illustrates the value of links from high PageRank pages.
Don’t game the system
I would be remiss if I didn’t point out that a single-minded focus on inbound links is fraught with peril, not the least because it might cause your pages to be removed from Google’s index!
Just as there are people selling weight loss products they claim don’t require dieting or exercise, there are people offering ways to inbound links that don’t require having real people link to you.
However, Google considers these shortcuts to be gaming the system and is ever vigilant to discover those cheaters. If caught cheating, Google will ban your pages from their index without notice.
The best way to gain inbound links for your key pages on your website is to do the hard work of creating a website with great content that people will want to link to. Read 15 Blogging Mistakes You Are Making on Your Company Blog to learn some cool tricks on this.
Architecture Matters
As an epilogue, getting inbound links is clearly necessary for high PageRank and thus good search engine results, but all those inbound links can be squandered without a good architecture and website management plan.
To ensure that your website’s great content and popularity get reflected in appropriately high search engine rankings, it’s critical to optimize your website’s architecture. More precisely, you need to be extra vigilant about your pages, and the URL design as well as make plans for how the URL structure might change over time.
The most under-realized aspect of SEO
Personally, I think the most under-realized aspect of white hat SEO is the lack of attention paid to URL design and planning, especially for larger websites. There are very few tools besides the low-level and effectively simplistic URL rewriters like mod_rewrite for creating and maintaining a URL plan. Very few articles exist that discuss URL design, and no articles I am aware of discuss URL planning.
However, I believe website owners will see huge improvements compared to their prior rankings if they focus on URL design and create a URL management plan. The good news is that URL design is mostly a one-time endeavor, assuming website owners adhere to the management plan, at least until there is a full website re-architecture.
But all of the whys and wherefores regarding URL planning and design are beyond the scope of this post, and instead will be the subject of many posts in the future. Stay subscribed!
Footnotes
- But remember it’s a secret, so we can’t know for sure.
- There’s more to search engine ranking than just PageRank, like applicable content. But PageRank differentiates pages that compete competitively for the same keywords.
- To those SEO-haters of the world, please note that I’m referring to those things that you can do with pure white hat techniques, things that if not done can result in a great website being given less credit by the search engines.
- Over time, I plan to address the lack of such articles and tools for URL planning and design.
