Differing numbers of pages indexed with and without the trailing slash

[ianmcintosh]

I noticed today that a site: query in Google (UK) for a certain domain I'm looking at returns different numbers depending on whether or not the trailing slash is added at the end. With the trailing slash the numbers are significantly different. This is a domain with a few duplicate content issues.

It seems very rare but I've managed to replicate it for a couple of other well known domains, so this is the phenomenon I'm referring to:

site:travelsupermarket.com - 16'300 results
site:travelsupermarket.com/ - 45'500 results

site:guardian.co.uk - 120'000'000 results
site:guardian.co.uk/ - 121'000'000 results

For the particular domain I'm looking at the numbers are 19'000 without the trailing slash and 800'000 with it! As mentioned, there are a few duplicate content issues at the moment that I'm trying to tidy up, but how should I interpret this? Has anyone seen this before and can advise what it could indicate?

Thanks in advance for any answers.

[AdamThompson]

The site: query on Google isn't a precise tool. It's not uncommon to see strange variances like that.

For a more accurate count, submit an XML Sitemap via Google Webmaster Tools and Google will give you a more precise count of which pages it has indexed.

[ianmcintosh]

Hi Adam, thanks for your response.

There is an XML sitemap submitted and GWMT shows a total number of indexed pages in the 800'000 region.

While I appreciate site: is not a precise tool, the fact that the site: numbers between trailing slash and no trailing slash match for virtually every other domain I try this with, and the numbers are so different in this example, suggests to me that this could be an indication of something amiss.

[AdamThompson]

"There is an XML sitemap submitted and GWMT shows a total number of indexed pages in the 800'000 region."

Brilliant. That's the number I would trust.

Incidentally, I see different numbers than what you see for all 4 site: queries you mentioned. Variances are pretty normal in my experience.

I've never noticed it, I would be intrigued to hear if someone else has correlated such variances to a technical issue or penalty.