If you only use one proxy IP to crawl a website, this will reduce your crawling reliability, geo-targeting options, and the number of concurrent requests you can make. Therefore, you need to build a proxy pool that can route requests and distribute traffic to a large number of proxies. This article will focus on the determinants of the effectiveness of a proxy IP pool.

The size of a proxy pool depends on many factors, as detailed below:

1. The number of requests you will make per hour.

2. The target website - large websites with more complex anti-bot countermeasures will require a larger proxy pool.

3. The type of IP you use as a proxy - data center, residential.

4. The complexity of the proxy management system - proxy rotation, throttling, session management, etc.

All 4 factors will have a significant impact on the effectiveness of a proxy pool. If you do not configure a proxy pool correctly for your specific web scraping project, you will often find that your proxy is blocked and you can no longer access the target website.