Why Do My E-commerce GSC Graphs Look Broken? Understanding the Sudden Impression Drop
If you've been overseeing SEO for an online store, chances are that around September 2025 your Google Search Console (GSC) graphs took a confusing turn. Impressions dropped steeply, average positions appeared to improve, and CTRs spiked upwards. For many e-commerce owners and marketers—especially those managing thousands of SKUs who depend on steady organic reach—this shift looked like a disaster waiting to happen.
The surprising part? It wasn't a penalty, nor was it a broad algorithm update aimed at e-commerce sites. Instead, it was triggered by a quiet yet highly significant reporting change: Google removed the &num=100 parameter. This setting had artificially inflated impressions for years by loading 100 search results per page, rather than the default 10.
This article explains what really happened, why it matters for your SEO reporting, and most importantly, how to adapt so your growth strategies remain accurate and reliable.
What Was &num=100 in Google Search and Why Did It Matter for E-commerce SEO?
For a long time, SEOs and rank-tracking tools leaned heavily on the &num=100 parameter. It instructed Google to show 100 search results per page instead of just 10. While this was convenient for crawlers—fewer clicks and faster data collection—it had an unintended side effect.
Google Search Console recorded impressions based on this expanded view. That meant if your product page sat buried on page 7 or 8, GSC still counted it as an "impression," even though no real shopper was scrolling that far.
For e-commerce brands, this distortion had three major consequences:
- Inflated impressions: A store reporting 200,000 monthly impressions might actually have been hidden deep in positions 60–90, far from real customer eyes.
- Worse average position: Since low-ranking URLs were included in the math, average positions looked poorer than they really were.
- Suppressed CTR: With impressions artificially bloated, clicks stayed flat, which dragged CTR percentages down unfairly.
In short, &num=100 painted a picture of "visibility" that was more illusion than reality.
What Changed in Google Search Console in September 2025 and Why Did Impressions Collapse?
When Google silently removed the &num=100 parameter, it effectively stripped away this distortion. Overnight, e-commerce dashboards began to shift:
- Impressions fell: often by 30–60%. This didn't reflect lost traffic, but rather the disappearance of phantom impressions from the depths of the SERPs.
- Average positions improved: those deep, irrelevant rankings were no longer skewing the data.
- CTR rose sharply: impressions dropped but clicks stayed consistent, offering a clearer view of engagement.
- Clicks remained stable: the key clue that customers were still arriving and converting as before.
For SEO managers, the graphs felt alarming, but the reality was simple—traffic didn't collapse, measurement got corrected.
Why Did My Impressions Drop? Real Case Studies From E-commerce GSC Data
To illustrate the shift, here are anonymized case studies from six e-commerce businesses. Each compares impressions from 7 Sept (before the change) and 12 Sept (after the change).
1 - Large Jewelry Retailer
7 Sept 2025 vs 12 Sept 2025
2 - Kidswear E-commerce Brand
7 Sept 2025 vs 12 Sept 2025
3 - Skincare & Beauty Brand
7 Sept 2025 vs 12 Sept 2025
4 - Pet Supplies Brand
7 Sept 2025 vs 12 Sept 2025
5 - Outdoor & Sports Retailer
7 Sept 2025 vs 12 Sept 2025
6 - Kidswear E-commerce Brand
7 Sept 2025 vs 12 Sept 2025
Key takeaways
Across six e-commerce sites, impressions fell between ~28% and 63% from 7 → 12 Sept 2025 after Google refined how it reports total impressions, especially reducing counts from low-visibility surfaces. Rankings and clicks for core queries generally did not decline at the same rate. Treat this as a measurement change, not a demand drop; validate impact using clicks, CTR, and conversions.