If your account has all three match types for a keyword (Broad Match, Phrase Match, and Exact Match), which one will catch the impressions from search users? It’s all down to the search query, the keyword and the matchtype. Looking at some examples will help explain. The basic rule is that the most precise match will win, so the order is Exact, then Phrase, finally Broad.

Assume that you sell paint for professional lawn mower racing. So you pick as the best keyword, “lawn mower racing paint”. In each of the three match types:

• lawn mower racing paint
• “lawn mower racing paint”
• [lawn mower racing paint]

Which search queries will be matched by each of these?

Exact Match

If the search query is only and exactly “lawn mower racing paint”, in upper, lower or mixed case (“Lawn Mower Racing Paint”) then the exact match will be *the* one to match. Even if you bid less for the exact match than for the Broad and Phrase match types, the impression will be sent to the Exact Match. Now, if the bid is too low for your advert to appear on Page 1, then you might have no impressions. That is, just because your search is matched, doesn’t guarantee appearing – but this is the keyword that would be matched, if the advert were to be offered.

This means that when you are writing adverts, if you were to put this keyword in its own AdGroup, you’d know exactly what the search query was that triggered the advert. That may be different than if you have possible qualifiers. For example, knowing that the search was for “ipod nano” only and exactly, means something different from “ipod nano scratch covers” – the adverts should be different.

Phrase Match

In the absence of an Exact Match match type, then the phrase “lawn mower racing paint” would match the phrase match variant rather than the broad match. The Phrase Match would also be the impression delivered for “lawn mower racing paint supplier” and “official lawn mower racing paint” and “official lawn mower racing  paint store”.

Once again note that if you have the Phrase Match keyword present, then if the bid is too low to appear, you won’t appear – even if you have the Broad Match keyword available and bidding high enough to appear.

Broad Match

If and only if you didn’t have the Exact Match or the Phrase Match keywords present in the account, then the Broad Match would be triggered for “lawn mower racing paint”. However, Broad Match will also capture:

• lawnmower racer paints
• mower repainting
• more points

Broad match, unlike the other types, will capture variations such as elisions (“lawnmower”), spelling mistakes (“mowr”, “peint”, “piant”) and does stemming (“paint” -> “paints”, “painting”, “repaint”, “repainting”). So even if you have Phrase and Exact Match keywords capturing impressions, you can still capture even more searches on Broad Match. As MrsC points out in her articles on Broad Match, effective use of Broad Match requires negative keywords to prevent low conversion rate searches from showing up, as well as the valid and useful search variations.