I thought I'd take the time to share some of the 10 free SEO tools  we use every day in our SEO efforts. Since all of these tools are vital to our SEO, I'm uber-grateful for their existence, and even more thankful that they're FREE. And seeing that these SEO tools are in fact free, the least I can do is pay-it-forward, promote them and pass along some link love.
Now, some of the free SEO tools on this list you may know about or use already, but hopefully you'll find some new tools you can use everyday in your own SEO efforts.
10 Free SEO Tools We'll Review:
- SEO for Firefox
- Majestic SEO
- Rank Checker
- Yahoo Link Domain
- Google Alerts
- Google Webmaster Tools
- The Free Keyword Tool
SEO for Firefox Toolbar - This SEO tool has become ingrained in my daily routine. So much so, that I forget it’s even a plug-in because it integrates so seamlessly with Google SERPs. I use it mostly as my private SERP data lab, to check SEO metrics like toolbar PageRank, site and page links, and twitter mentions in the SERPs. SEO for Firefox also displays on-page nofollow links too, which is a time saver for link building  and analysis. You get to see social bookmarking instances, Alexa rank, cache date, Wikipedia mentions and a host of other cool factors too.
Majestic SEO  - I’m a big fan of Majestic SEO, which quickly has become an invaluable SEO tool for measuring link acquisition. One of my favorite features is the "daily update," which updates you each day with a journal of new inbound links. The only downside to this is Majestic also discovers every paid link in your sponsored campaigns, so you'll be sifting through a lot of transient, garbage links. Other notable features include some pro tools for charting link discovery, so you can impress clients with fancy bar charts. Also, the Majestic SEO site just got a facelift, which looks much slicker than the previous skin. Nice work, guys!
Rank Checker  - Are you obsessed with where you site ranks in engines? Hey, me too! Well, with SEO Book's Rank Checker you can get your daily rank fix from the Big Three (Google, Yahoo, Bing) simultaneously. This free SEO tool then lets you export the results to Excel and incorporate them into a keyword ranking  report. What's also nice is Rank Checker gives you the ability to add multiple keywords  in a data dump and save the reports as presets, so you don't have to enter in your keywords each time.
iGoogle - Did you know you can customize your iGoogle dashboard and create a fantastic brand monitoring tool? Check out the screenshot below where you'll see I've set my iGoogle to capture brand mentions from the Twitter search feed, any forum mentions and blog references. How does this help SEO you ask? Besides the all important reputation monitoring, my customized iGoogle dashboard also serves as another link finder. You see, where there are brand mentions, there are often links, or even new link opportunities.
Yahoo Link Domain - I typically access Yahoo Link Domain through the SEO for Firefox display and use it primarily to analyze inbound links to deep pages on my sites, as I'm manually checking keyword rankings. The other way I use Yahoo Link Domain is to look at SERP competitor link profiles to find linking patterns, trends and more so to uncover linking opportunities for my own sites. If you're looking to take your site analysis even further, Bruce Clay has a fantastic list of advanced search operators for Yahoo  that you should check out. Bonus tip: with the SEO for Firefox plugin enabled, you can export these Yahoo Link Domain results into Excel by clicking the "100" link, then the "CSV" link in the screenshot below and sort by PageRank , if you're so inclined.
Foxyrank  - This is a pretty new add-on for Firefox, but a great free SEO tool nonetheless. With a click, Foxyrank evaluates the webpage you're on and presents PageRank, valid links (internal and external), and most importantly (for me anyway) how much "juice" each link on page is passing. Foxyrank also gives you the option to mark (highlight) all the valid external and internal links on page. I love it because it's a great way to evaluate potential targets for link building and determine (hypothetically) which PR 4 page is passing more juice, so I can really refine and better qualify potential link targets.
Google Alerts - I use Google Alerts as an SEO tool to monitor anyone talking about my target keywords or anyone writing or posting about competitors. Anytime I see a post on my target SEO keyword , I see it as an opportunity to reach out to the blogger and put WordStream on their radar, which creates opportunities for future posts about us because experience has shown that if the author likes writing about our niche or our competitors, chances are that person will write about us. And where there's content, there are back links. (If Google Alerts isn't working , you might want to reconfigure it.)
Ping.fm  - Tired of waiting for your new content to get indexed? Ping.fm gets new content indexed fast. The platform is actually meant for posting a single message to more than 40 different social networking sites at once. But I use it primarily to push new content to social sites because they're constantly getting crawled, which means my content gets found much faster and indexed by the engines often in a matter of hours rather than days. And the faster your content gets indexed, the faster it ranks. Sure it's a little spammy, but my intentions are good. Twitter purists, don't fret. I never use Ping.fm for mass Tweeting.
Google Webmaster Tools - This free SEO tool gives me valuable insights into my visibility in the SERPs and key performance metrics. The two features I use the most are the organic click-through-rates of my top 100 pages and the internal links analysis, so I can discover and track which pages on my site are pointing to one another. Google Webmaster Tools also publishes your inbound links too, but Yahoo Link Domain does a more thorough analysis, while Majestic SEO is the most comprehensive in my opinion. Also, Google, if you're listening, the ability to identify nofollow inbound links and filter them out of results would be a bonus.
Twaitter  - Twaitter is a free service for sending out scheduled or recurring Tweets (I know repeat tweeting is blasphemy, but hear me out). You can set it to distribute your message daily, weekly or monthly at the exact minute you want it published, which is a big time saver. I use it mainly to send out Tweets that bear repeating. For example, I use Twaitter to repeat Tweet job postings, contest announcements or recurring events, like the one in the screenshot below for my buddies at SEM Synergy on Webmaster Radio. So how is this relevant to SEO and a free SEO tool? Well, promoting other people's events and material is a pretty nice thing to do and being nice can often get you a link or two ;).
Bonus SEO Tool - The FREE Keyword Tool  - One final SEO tool we use every day is our own FREE Keyword Tool, which is the fastest, most accurate, most comprehensive keyword suggestion tool  available. The FREE Keyword Tool aggregates over 1 billion unique keywords, representing over a trillion search queries, and hundreds of millions of related terms from diverse keyword sources. You can get thousands of long tail keywords  suggested, determine keyword competition  with the relative volume feature, and it's always completely free.
10 Free SEO Tools: What's in Your Tool Bag?
So there you have it. These are the primary FREE SEO tools we use every day to help make our SEO management  efforts more effective and efficient here at WordStream. If you have any free SEO tools, like your favorite keyword tool , keyword finder  or keyword generator  you want to share, please feel free to add them in your comments below. Because we're always on the prowl for new search marketing tools  and would love to hear about your favorites.