NoIndexing Massive Pages all at once: Good or bad?

[WebServiceConsulting.com]

If you have a site with a few thousand high quality and authoritative pages, and tens of thousands with search results and tags pages with thin content, and noindex,follow the thin content pages all at once, will google see this is a good or bad thing?

I am only trying to do what Google guidelines suggest, but since I have so many pages index on my site, will throwing the noindex tag on ~80% of thin content pages negatively impact my site?

[Dr-Pete]

If you're not currently suffering any ill effects, I probably would ease into it, just because any large-scale change can theoretically cause Google to re-evaluate a site. In general, though, getting these results pages and tag pages out of the index is probably a good thing.

Just a warning that this almost never goes as planned, and it can take months to fully kick in. Google takes their sweet time de-indexing pages. You might want to start with the tag pages, where a straight NOINDEX probably is a solid bet. After that, you could try rel=prev/next on the search pagination and/or canonical search filters. That would keep your core search pages indexed, but get rid of the really thin stuff. There's no one-sized-fits-all solution, but taking it in stages and using a couple of different methods targeted to the specific type of content may be a good bet.

Whatever you do, log everything and track the impact daily. The more you know, the better off you'll be if anything goes wrong.

[MoosaHemani]

At the moment you are in Google but not really following the Google guidelines as far as the thin content is concern... once you will apply the rule you will be more nearer to Google guidlines which simply means Google will love you more...so no big problems!

You might see a lil ups and downs in traffic but it will be ok within days of time!

[CleverPhD]

It may take a while when the pages you are deindexing are not crawled as often by Google.  You just have to sit back and wait a bit.

Two other points.

Look in your Analytics.  If you delete all those pages, how much traffic do they bring in to start with?  If it is only 5% of traffic, then expect to lose that much.

One correction on the use of robots.txt vs the meta tag.  Robot.txt stops Google from crawling, but will not remove pages from SERPs.  Noindex meta tags on page will get them removed.  Use the former and you will be happier.

[WebServiceConsulting.com]

As far as google crawling and de-indexing all of the pages with the noindex tag, is that a time consuming process before all of the pages are removed?

[jesse-landry]

No negative impacts here as far as penalties or otherwise. Just make sure it's really what you want to do. If the page would ever be searched for by a user then keep it indexed regardless of how thin you worry the content might be. Or beef it up.

Also consider using your robots file instead of having to add that tag to all these pages...

-my two cents.