Using a sitemap can help Google find its way throughout your site to make sure every page is indexed. It can also give you a table of contents, if you skin it for human consumption. They’re versatile tools, but all too many people treat them as hammers when they’re much finer instruments. Have you ever considered using multiple sitemaps?
A sitemap, at its most basic, is nothing more than a file with links to every page on your site. More structured sitemaps add additional data, such as the date of the most recent change and some basic organization.
There are two primary types of sitemap; the XML and the HTML. The XML sitemap is pure data and is only used by – and generally only visible to – the search engines. If a user stumbled across an XML sitemap, it wouldn’t make much sense. The HTML sitemap is an attempt to take the data of an XML sitemap and present it in a meaningful way. Blog archive pages or a table of contents page would be appropriate examples.
Sitemaps can also specify some data about a page. Particularly, a page hosting a video can specify in the sitemap the category, age rating and running time of the video. An image page can specify the content of the image, the license and other data. This is not required, but it may be helpful to index the multimedia on your site.
How can you use sitemaps in different scenarios? Google says that you don’t necessarily need a sitemap at all, particularly for small sites. However, in some circumstances, it can come in handy.
• Large sites, any site with over a couple hundred pages, can benefit from a sitemap. It helps keep the search engine from overlooking important pages. A sitemap that specifies how often a page changes will help Google come back to index content when it changes, rather than hope to find those changes when a reindex occurs.
• Any site that has content that is not well linked or that is otherwise isolated from the site as a whole can benefit from a sitemap. Google needs links to find content to index; a page with no incoming links is effectively invisible unless Google is told where it is. A site with a lot of pages with few or no incoming links would benefit from telling Google where those pages are.
• Brand new sites can benefit from a complete site map for the first indexing. This helps you ensure that every page on your new site is indexed, despite any broken links that would otherwise cut off large parts of the site.
• Sites that feature in Google News, rich media or another location where sitemap data may be useful. When you provide Google with extra data about the updates to your pages, the search engine can then use that data to benefit you in search.
What are the pros and cons of using sitemaps in various configurations?
Not having a sitemap at all is generally a negative. For one thing, there’s no reason not to have a sitemap. It’s purely beneficial, and at worst, it’s just one extra file on your site. The only reason to avoid implementing a sitemap is if you simply can’t spare the time to keep it up to date. This is hardly a concern, due to the proliferation of automatic sitemap generators available.
You can get away with using no sitemaps on small sites that are well linked. You can also get away with it if your site rarely updates or is abandoned. These are edge cases, however.
The most common use for sitemaps is just to have one singular sitemap that indexes every page on your site. It’s easy to generate one sitemap and it’s easy to keep that sitemap up to date. It’s likewise easy to submit that sitemap to Google.
Using one singular sitemap helps keep all of your pages in one place. It’s also useful if you want to draw on the XML data to make an HTML sitemap usable by your readers. You don’t need to skin an XML sitemap in this manner, of course; Google can read an HTML sitemap just as easily.
Why might you not want to use a single sitemap? In large sites or sites that update frequently, the sitemap can grow old and out of sync. On extremely large sites, the file can be so large it stalls out browsers trying to load it, though this is extremely rare.
Did you know you can use more than one sitemap? There are a few ways to set this up. You can divide your site into sections and create sitemaps for each section. You can create sitemaps for different types of page – blog posts, product pages, landing pages, etc. You can separate it chronologically, indexing every few hundred pages in a sitemap and then creating a new one for the next few hundred pages.
This benefits you over using a single sitemap in one major way; it can help with full-coverage indexing. Google will occasionally stall out while indexing through a sitemap and may leave some parts of it unparsed. It’s not a guarantee that using multiple sitemaps will benefit you in this manner, but it typically does not hurt.
Another benefit to using multiple sitemaps is content segmentation. If you find that some pages on your site are not being indexed, you can use multiple sitemaps to diagnose where the problem lies. This is best used as a technique for massive sites where diagnosing link and code issues is very difficult and time consuming.
To implement multiple sitemaps, you should first generate one complete XML sitemap. You can then break this up into multiple files, individual sitemaps for general categories or whatever division you chose. Once you have generated these individual sitemap files, you will want to put them in a subfolder on your web host. In your root directory, you will have one file, the sitemap index. To create a sitemap index, you essentially create a new sitemap that only indexes the other sitemaps. You can find instructions here.
Multiple sitemaps aren’t for everyone. One sitemap, kept under 10mb in size, can hold up to 50,000 links without breaking. Multiple sitemaps are a luxury, not a necessity, for search indexing.