SERP Scraping Costs Surge: Google Removes &num= Parameter

Google recently discontinued the long-standing `&num=` parameter, a crucial feature that allowed users to specify the number of search results displayed per page, typically used to retrieve up to 100 results at once. This removal marks a significant shift for the SEO industry, particularly impacting services and tools that rely on large-scale SERP (Search Engine Results Page) data scraping.

The primary implication of this change is a substantial increase in the cost and complexity of SERP data collection. Previously, scrapers could fetch a large volume of results (e.g., 100) with a single request using `&num=100`. Now, without this parameter, data providers are limited to Google’s default page display, which is typically 10 or 20 results. To gather the same amount of data, they must perform significantly more requests, often navigating through multiple result pages. This exponential increase in requests directly translates to higher operational costs due to increased API calls, bandwidth consumption, and processing time. For businesses heavily reliant on comprehensive SERP data, this means either absorbing higher expenses, reducing the scope of their data collection, or investing in more sophisticated, and often more costly, scraping infrastructure.

From Google’s perspective, removing `&num=` likely serves to mitigate resource drain from automated scraping and makes it more challenging for third parties to extract vast amounts of data efficiently. This move enhances Google’s control over how its search results are accessed and utilized by external entities. While not explicitly a “benefit” for the industry, it’s a strategic move by Google to manage its infrastructure and data dissemination.

A specific example of this impact is seen in platforms like Moz Pro. Moz, which relies on extensive SERP data for its tools, has had to adapt its data collection methodologies. The removal of `&num=` means they can no longer efficiently pull 100 results per query. Consequently, Moz and similar services must make more frequent and numerous requests to collect comparable data volumes, affecting their internal processes, data freshness, and potentially their service offerings or pricing models. This industry-wide change fundamentally alters the economics and technical approach to SERP data acquisition.

(Source: https://moz.com/blog/num-100-and-changing-serp-lengths-in-moz-pro)