Class C Checker

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Backlinkwatch

Reciprocal Link Cheker

Find IP address - Check IP Address - Test Class C IP Address


 Google Webmaster Tools
Google Webmaster tools is the equivalent of a mechanic looking after you car daily but for websites of course. Identify broken links, malware and other issues and find out what search queries lead to your pages even with clickthrough statistics. It even checks your website speed and tells you why it’s too slow.
Google Analytics
In case you still don’t know GA you have probably slept for years. Some SEOs don’t use it due to paranoia of being controlled by Google though. You have to decide yourself what’s more important, a very useful analytics tools or the fact that Matt Cutts can look under your skirt.
Google Website Optimizer
With Google Website Optimizer you can test different versions of your pages. This way you can determine the best converting ones. It’s called A/B split testing or multivariate testing and is all the rage lately in SEO circles and beyond.
Google Zeitgeist
Google Zeitgeist is not a tool in the strictest sense but you can use it keyword research nonetheless. In fact it shows the most popular queries so it’s a good starting point in your SEO campaign. Take the Zeitgeist popular keywords and then test some keyphrases containing them with the other tools that will follow in this list. Also checkout the current Zeitgeist aka Hot Trends.
Google Trends
Google Trends lets you compare traffic for popular search terms and websites. This way you can determine whether a topic is rising in popularity or not. Works gret combined with Google Zeitgeist and Google Insight for Search
Google Insights for Search
Insights for Search is like Google Trends on steroids. You can look up most keywords here, even those that aren’t popular at all. Compare up to five keywords and their ensuing traffic.
Google Traffic Estimator
This is a classic tool. It says “Adwords” but you can use it to find out the probably number visitors a keyword can bring to your site.
Google Keyword Tool
The Keyword Tool is like the Traffic Estimator but from a differnet angle. Some people prefer this others prefer that. You’ll want to check both to make sure you’re on the right track with your keywords.
Google Search Based Keyword Tool
This very neat tool allowas you to find out related keywords to a site or existing keyword or rather both. It’s connected to Google Insights for Search is a very useful way.
Google Ad Planner
Google Ad Planner is like Alexa and SpyFu in one. Use it to screen popular sites or your competitors for keyword intelligence or both.
Google Alerts
Enter a search term or domain (your website for example) that you wish to track and Google will notify you each time when it finds a new reference on the Internet
Google AdWords Keyword Suggestion Sandbox

If you want to run an Adwords you should consider Google's keyword suggestion tool. It will offer a bunch of similar keywords and thus help you optimize your ad spendings
Google Suggest

Start typing in the search query and Google will suggest similar search terms and tell you how many results you get for each term
Google Sponsored links

Do a search in Google and display sponsored link results only. Extremely useful when you are trying to find the proper wording for your Adwords or want to see how the competition is doing
Overture's search term popularity tool

Query Overture's database and find out how many search queries did a keyword get last month. Useful for selecting which keywords to target
Touchgraph Google Browser

Type in a URL and see which sites are related to it in a 3D graphic view. Requires Java