Broad Match

Broad match is the most permissive of the three Amazon PPC keyword match types. A broad-match keyword triggers on any shopper search query that contains its root tokens in any order, plus synonyms, plurals, misspellings, close variants, and (since 2022) related terms Amazon's relevance model considers semantically adjacent.

The strategic job of broad match is discovery. It is not a profit layer — it is the engine that surfaces new search terms which are then harvested into Exact Match campaigns. An account without broad-match campaigns has no way to find new keywords.

How broad match expands

Bid keyword: stainless steel water bottle. Will match:

• steel water bottles (token order changed, plural)
• insulated stainless bottle for water (extra tokens, reordered)
• water bottle stainless steel (reorder)
• metal water bottle 1L (synonym substitution — "metal" for "stainless steel")
• vacuum sealed steel bottle (close-variant relevance)

A single broad-match keyword can fan out to 40+ unique search terms per week. That fan-out is the data source for the harvest loop.

Bidding for broad

Broad-match CVR is structurally lower than exact-match CVR for the same root keyword — typically 30–60% lower because the matched queries include lower-intent variants. The base bid follows the same formula but with the lower CVR:

Broad Bid = ASP × CVR_broad × Target ACOS

In practice, broad bids land at 30–50% of the equivalent exact bid. Bidding the same across both match types systematically over-pays for broad and under-pays for exact.

Broad match and Target ACOS

Discovery campaigns should run on a higher Target ACOS than profit campaigns — often Target ACOS × 1.3 to 1.5 — because their job is to find winners, not to convert efficiently. A broad campaign running at the same Target ACOS as the rest of the account will starve and produce too few search-term observations to be useful.

The harvest loop, broad's role in

1. Broad-match keyword in a discovery campaign matches dozens of shopper queries.
2. The Search Term Report reveals the winners.
3. Winners are promoted to a manual Exact Match campaign at math-derived bids.
4. The harvested terms are added as Negative Exact keywords on the broad parent.
5. Repeat weekly.

Without step 4, the broad campaign keeps bidding on terms the exact campaign is already winning, doubling spend per conversion. The negation step is what makes broad match economical at scale.

Common mistakes

• Treating broad like a profit layer. Broad is intentionally inefficient. Judge its performance by harvest yield (new winning terms per week), not by its standalone ACOS.
• No negative cycle on the broad parent. Spend leaks indefinitely on harvested terms.
• Bidding too low. A broad campaign with bids matched to its CVR but below the auction floor never gets impressions, never produces search-term data, never feeds the harvest loop. There is a minimum viable broad bid below which the campaign is just dark.
• Single broad ad group with too many seed keywords. 30+ seed keywords in one ad group make the resulting STR untraceable. 5–15 themed seeds per ad group is the workable range.