On the other hand, there are many analogous strategies that developers can use to avoid these blocks as well, allowing them to build web scrapers that are nearly impossible to detect. Here are a few quick tips on how to crawl a website without getting blocked. You can visit here; Web scraping without getting blocked.
The number one way sites detect web scrapers is by examining their IP address, thus most of web scraping without getting blocked is using a number of different IP addresses to avoid any one IP address from getting banned.
To avoid sending all of your requests through the same IP address, you can use an IP rotation service like Scraper API or other proxy services in order to route your requests through a series of different IP addresses. This will allow you to scrape the majority of websites without issue.
For sites using more advanced proxy blacklists, you may need to try using residential or mobile proxies, if you are not familiar with what this means you can check out our article on different types of proxies here. Ultimately, the number of IP addresses in the world is fixed, and the vast majority of people surfing the internet only get 1 (the IP address given to them by their internet service provider for their home internet), therefore having say 1 million IP addresses will allow you to surf as much as 1 million ordinary internet users without arousing suspicion.
This is by far the most common way that sites block web crawlers, so if you are getting blocked getting more IP addresses is the first thing you should try.
Set a Real User Agent
User Agents are a special type of HTTP header that will tell the website you are visiting exactly what browser you are using. Some websites will examine User Agents and block requests from User Agents that don’t belong to a major browser.
Most web scrapers don’t bother setting the User Agent, and are therefore easily detected by checking for missing User Agents. Don’t be one of these developers! Remember to set a popular User Agent for your web crawler. For advanced users, you can also set your User Agent to the Googlebot User Agent since most websites want to be listed on Google and therefore let Googlebot through.
It’s important to remember to keep the User Agents you use relatively up to date, every new update to Google Chrome, Safari, Firefox, etc. has a completely different user agent, so if you go years without changing the user agent on your crawlers, they will become more and more suspicious.
It may also be smart to rotate between a number of different user agents so that there isn’t a sudden spike in requests from one exact user agent to a site (this would also be fairly easy to detect).