If you are going to invest hundreds or thousands of dollars a month in pay-per-click advertising, you will probably want to know what your competitors are doing. How much are they spending? What keywords are they bidding on? What do their ads look like? Luckily there are quite a few resources to find out some of that information including SEMrush, iSpionage, and SpyFu. Instead of giving you a comparison between those three, I'd like to give you an overview of what you can and can't do through a competitor analysis.
You can't: Get exact information. They spy tools do not have access to your competitors' accounts. They can run searches on Google and see what ads show up. They can estimate the cost-per-click based on Google's keyword tools. But they can't see actual data. Here's what they say about one of my client's advertising for June 2016:
Actual: 2,919 clicks, $5,232 spend
Spyfu: 6,050 clicks, $2,230 spend
iSpionage: 10 clicks, $504 spend
SEMrush: 691 clicks, $975 spend
(This one was a hard one for the research tools to get a handle on because it's a non-profit and many of the words we bid on are informational and are therefore rarely bid on. The research tools would do better on an e-commerce site where there is more competition and data.)
You can: Get a good summary of the most important keywords. Google gives information on how many times a search is made, and the spy tools run those searches and see whose ads show up and in what position. This information can help you come up with keyword ideas of your own.
You can: See trends in competitors marketing spend. Although the absolute spend data may be wrong, these tools are generally pretty good at telling you when competitors increase or decrease their spend significantly.
You can't: See specifics. They can show you what searches your competitors' ads show up for, but they can't tell you if they have that search as an exact match keyword or if Google matched it with a broad-match keywords. They can't tell you the quality score, so you can't tell if they have a high position because they are bidding really high or have a really high quality score.
You can: See your competitors' ads in one place. Use this for ideas on what to put in your ads!
You can: Get enough information it will make your head spin. Make sure you are focused on getting the important information--the data that will improve your account--and ignore the rest.
Want to learn more? Each of those tools gives you find some data for a few websites each day. Visit the sites, plug in a couple of your competitors and find out what they are doing.