If you are managing a Google AdWords marketing campaign, it is critical to employ negative keywords. This is particularly true if any of the keyword phrases in the ad campaign are broad- or phrase-matched. Negative keywords cause an ad to not be shown if any of those keywords are in the search phrase. This is important for a few reasons. First, because the ad will not be shown for keyword phrases that are not relevant, there will be fewer click-throughs that do not convert to sales. Second, the overall CTR (click-through rate) will be higher because there will be fewer instances of searchers viewing the ad but not clicking. The higher CTR will cause the ad to attain a higher position without requiring a higher CPC (cost per click). This will save you money and increase the ROI of your Google AdWords marketing campaign.
Let's look at an example. Suppose an online store sells organic food. The store's Google AdWords campaign has an ad group with these broad-matched keywords:
organic food
organic food store
Using at least one keyword research tool (and preferably more) will reveal many keyword phrases that are searched on that contain the phrase "organic food" but are clearly not related to purchasing organic food for people to eat (as opposed to pets). For example, using the Overture (Yahoo) search term suggestion tool yields these results for the keyword phrase "organic food":
24904 organic food
1286 organic dog food
1243 organic food store
1020 organic baby food
689 organic pet food
685 organic food online
465 organic cat food
373 benefit of organic food
It would likely not benefit the online store that's selling organic food for people to eat to display an ad next to search results for the keyword phrase "organic dog food". Adding "-dog" to the AdWords ad group will prevent the ad from appearing for that particular search phrase. Keep in mind that the Overture search term suggestion tool usually does not differentiate between singular and plural forms of keywords. From this list, here's how to set up negative keywords for the Google ad campaign:
-dog
-dogs
-baby
-babies
-pet
-pets
-cat
-cats
-benefit
-benefits
Only place one negative keyword per line. Precede each keyword with a dash; the preceding "-" indicates to the Google AdWords system that the keyword to follow is a negative keyword. If any of the negative keywords are in a search phrase, the ad will not appear next to the search results.
If the online store sells organic baby food, it is still worth including "-baby" and "-babies" for this general "organic food" ad group example. A separate ad group could be created for items as specific as organic baby food. Each ad group should have a very tight focus. Include both the singular and plural forms of negative keywords as people often search using both. For example, "buy organic baby food" or "buy organic food for babies" are both searches that would cause an ad to be shown for a Google AdWords ad group, containing "organic food" as a broad-matched keyword phrase.
The list of negative keywords for an ad group should evolve. Start with a list derived from a handful of keyword tools but add to the list over time. The web logs for your web server are an ideal source for discovering new negative keywords. Whether you sift through the raw web logs or have a web statistics program to access the log data, be sure to examine the searches yielding hits from your ad group. For example, if you see a search in the logs for "organic food gives me gas" then add "-gas" as a negative keyword. Often, there are hundreds of unique searches that people perform that do not show up in any keyword research tool. Gradually build up your list of negative keywords to avoid receiving traffic that will not convert to sales.
