Adding an extra keyword or two might start simply enough. Try a few out and see what converts. What’s the harm in that? But soon, extra weight tugging at your budget keeps you from maximizing your focused messages that convert. Using negative keywords can help trim this fat from your Adwords campaign.

What are negative keywords?

Negative keywords tell Google not to show your ad when they are entered as a query. If you sell specialty seeds and write a gardening enthusiast’s blog, you want people to find you when they search for “heirloom tomatoes.” What you don’t want is for someone to see your ad when they are hunting for “heirloom tomato recipes.” That is where negative keywords come in. Enter “-recipes” into your Google Adwords lineup to remove your ads from those related results.

Successful search marketers agree, the best ads specifically answer what is being searched for. That is why popular negative keyword suggestions are “-free trial,” “-repair” and “-discount” unless you are able to provide those.

Even negative terms about a brand are important to consider. When your business revolves around Neon Widgets, it’s best to avoid having your ad show up for “Neon Widgets suck.” Anyone searching for that phrase is simply not your buyer.

Accidental traffic is good if they stumble upon your blog, but if you are paying for each click of an ad, you want every visitor primed to buy.

So how does SpyFu help you discover negative keywords that could be overlooked?

You might already be advertising on terms that are irrelevant to your business. But if Adwords campaigns are made of terms you input, how could that possibly happen?

That’s exactly what this next advertiser thought.

SpyFu Kombat allows you to compare up to three domains’ keyword lists (both organic and paid) at a time. The resulting diagram sorts common keywords between two competitors, common keywords between all three competitors, and keywords exclusive to any of the domains.

Here we are comparing three big players in online shoe sales: Zappos, Piperlime, and Shoes.com.

I clicked on the section of piperlime.com’s unique ads, giving me 185 terms. Look at #5.

Piperlime, a shoe seller, showed up as an ad result for “autodesk 3d studio max,” software usually used in game design. Here’s a stellar example of a negative keyword idea they never would have considered on their own.

The explanation was simple:

1. Click on the keyword to drill into its details. This opens the term page.
2. Select the option to “View this keyword’s history.”
3. Running down the list of all domains who have advertised on that term, we can spot piperlime.com in July 2008. One click solves the mystery.

“Max Studio” shoes is a relevant keyword for piperlime.com. Since they can deliver this popular shoe brand, it works well for them. Unfortunately the ad triggered an irrelevant match. No better remedy than a negative keyword. Welcome to the lineup, “-autodesk 3d.”

By running piperlime.com into SpyFu Kombat, we were able to pinpoint terms that might have come to haunt them down the road.

Yes, it is possible to run only your own domain in SpyFu. But by entering related competitors into Kombat at the same time, you filter out relevant keywords so that you don’t have to sift through so many to find the “autodesk 3d’s” of your niche. It’s a shortcut.

Kombat automatically creates the keyword list that is exclusive to your domain. In the example above, Shoes.com and Zappos might have also advertised on “Max Studio” as well as “leather boots” and “Steve Madden shoes.”

So instead of scouring through hundreds of keywords that triggered your ad, you narrow it down to the accidental fat most likely to waste your money. And saving time here saves you time and money in the long run. Goodbye, fat.