Zyte Smart Proxy Manager(formerly Crawlera) is slow on standard web browsers.

The reason is that it's not the way it's intended to be used. Unlike a standard proxy, Smart Proxy Manager is designed for crawling and throttles requests speed to avoid users getting banned or imposing too much load on websites. This throttling translates to a perception of Smart Proxy Manager being slow when tried in a web browser. Continue reading to understand why.

When you access a web page in a browser, you typically have to download many resources to render it (images, CSS styles, JavaScript code, etc.) and each resource is a different request that needs to be performed against the site. Compare this to crawling, where you typically only download the page HTML source. Not only do you need to perform many requests to render a single page, but web browsers also limit the number of concurrent requests performed to any single site. All this translates to Smart Proxy Manager looking slow when tried from a web browser. But this "slowness" is actually a feature for the purpose that Smart Proxy Manager is intended to be used.