PMAX Strategy: 90-Day Conversion to Search/Shopping

Overview

Performance Max (PMAX) campaigns are best used as a learning tool, not a permanent campaign structure. The core principle: run PMAX for approximately 90 days to gather broad performance data across Google's inventory, then migrate to more targeted Search and/or Shopping campaigns using what was learned.

This approach avoids the long-term inefficiency of PMAX — which "spends a bunch of money trying things" — while still benefiting from its cross-channel discovery capability early in a product's advertising lifecycle.

"You use PMAX to figure out what works, and then you convert it to other types of campaigns."
— Mark Hope, 2026-03-25 weekly call

The Strategy

Phase 1: PMAX (~90 days)

Launch a PMAX campaign for a new product or product group
Connect the Google Merchant Center feed so Shopping inventory is included
Set a realistic target CPA based on expected performance (adjust as data comes in — see ^[1])
Add videos in the correct aspect ratios (landscape and vertical) to all PMAX asset groups — missing video is a common cause of low optimization scores
Monitor performance; do not over-optimize prematurely

Phase 2: Migration to Search/Shopping

After ~90 days of data, identify which keywords, audiences, and product types are converting
Build dedicated Search campaigns for high-intent keyword clusters
Build Shopping campaigns for top-performing SKUs
Pause or reduce PMAX budget as the replacement campaigns ramp up

Campaign Structure Principles

Dedicated Product Campaigns

Maintain separate PMAX (or Search/Shopping) campaigns for your highest-volume products. In the Doodle Farms account, these are:
- Black Beans
- Popcorn (Doodla and Old World)
- Yellow Cornmeal

Each has distinct CPA targets and budget needs. Bundling them obscures performance signals.

Catch-All Campaign

Any products not covered by a dedicated campaign should be captured in a low-budget catch-all Shopping campaign. This ensures full catalog coverage without diluting budget from priority products.

In the 2026-03-25 audit, 58 Doodle Farms products were completely unadvertised — invisible in Google Shopping
A catch-all campaign with a modest daily budget addresses this gap
Think of it as a safety net: low bids, broad coverage, no wasted impressions on untargeted SKUs

"You don't want to let stuff slip through. It's kind of like the old gold banner."
— Mark Hope, 2026-03-25 weekly call

PMAX Asset Requirements

Low optimization scores on PMAX campaigns are frequently caused by missing assets. Required assets for a healthy PMAX campaign:

Asset Type	Notes
Videos	Must include correct aspect ratios (landscape 16:9 and vertical 9:16). Build in Canva or use Google's in-platform video builder as a starting point.
Images	Lifestyle images preferred; ensure correct dimensions for each placement type
Headlines & Descriptions	Multiple variations required
Logo	Must meet dimension requirements (2:1 ratio recommended for horizontal logo slot)
Site Links	Set at account level to cover all campaigns efficiently
Call-outs & Snippets	Free real estate — always add these; missing them wastes ad space

Bid Strategy by Campaign Type

Campaign Type	Recommended Bid Strategy
Brand Search	Target Impression Share (95% absolute top) — never leave brand searches on the table
PMAX (learning phase)	Target CPA set to realistic observed CPA, not aspirational
PMAX (mature)	Migrate to Search/Shopping with Maximize Conversions
Catch-All Shopping	Maximize Clicks with a low budget cap
Old World Search (new)	Start with Maximize Clicks; switch to Maximize Conversions after sufficient conversion data

Key finding from 2026-03-25 audit: The Doodle Farms Black Beans PMAX had a target CPA of $17 but the actual observed CPA was ~$30. Underbidding relative to reality causes the algorithm to under-serve the campaign. The target was raised to $30 to align with actual performance.

Optimization Score & Impression Throttling

Google throttles impressions for campaigns with an Optimization Score below 80%. During the 2026-03-25 audit, the Doodle Farms account was at 60% — a significant risk to delivery.

Common fixes that raise score without increasing budget:
- Add missing videos to PMAX asset groups
- Add site links, call-outs, and structured snippets (set at account level for efficiency)
- Fix broken conversion tracking (uncounted conversions suppress smart bidding)
- Align target CPA with observed CPA

Target: above 80% as a floor; above 90% as a goal. Getting from 90% to 100% typically requires budget increases, which may not be warranted.

Conversion Tracking Is a Prerequisite

PMAX and smart bidding strategies are only as good as the conversion data they receive. A broken tracking setup will cause the algorithm to optimize toward nothing.

Example from 2026-03-25 audit (Doodle Farms Display Remarketing):
- Campaign was spending ~$300/month with 0 reported conversions
- Audit revealed 574 conversions were occurring but not being counted due to a tracking misconfiguration
- The campaign was rebuilt to target cart abandoners with all-product messaging (replacing a beans-only focus)

Always verify:
- Conversion actions are set as Primary (not Secondary) where appropriate
- Tags are firing correctly on thank-you/confirmation pages
- No duplicate or conflicting conversion actions

See also: ^[3] for a parallel case of broken conversion tracking causing zero reported conversions on a $33/day spend.

Gilbert: Launch new PMAX campaign for Old World products (connect Merchant Center feed)
Gilbert: Create catch-all Google Shopping campaign for the 58 untargeted Doodle Farms products
Gilbert & Karly: Create/upload PMAX videos in correct aspect ratios for all low-score campaigns
Ongoing: Monitor existing Doodle Farms PMAX campaigns (Black Beans, Popcorn, Cornmeal) for migration readiness to Search/Shopping

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