Match types tell Google how closely a search must match your keyword for your ad to show. Broad is the widest; exact is the narrowest. Picking wrong either starves you of volume or wastes spend on irrelevant clicks.
Search must match your keyword or a close variant. Most control, least volume.
Keyword: [red running shoes] → matches "red running shoes", "running shoes red", similar intent.
Search must include your phrase (or close variant) as a subset. Medium control.
Keyword: "red running shoes" → matches "buy red running shoes", "red running shoes for marathon", phrase in there.
Search includes anything Google thinks is related. Widest reach, least control. Modern broad match uses AI to find related intent.
Keyword: red running shoes → matches "running gear", "jogging footwear", "athletic shoes red", loosely related.
Google has nudged advertisers toward broad match + smart bidding. Works when:
Without those, broad match burns budget.
Broad match discovers irrelevant queries constantly. Weekly: review the search terms report, add negatives for queries that don't fit.
Run exact match for your proven high-ROI keywords (tight control) + broad match with smart bidding for discovery (find new queries). Exact match gets priority when both could trigger.