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KellyrContiq
KellyrContiq

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How to Extract Data from a Website?

Are you looking for ways to extract data from a website online? Then keep reading to discover the many ways you can turn web content into useable data.

Extract Data from a Website The Internet has long become the biggest source of global information. For every minute that passes, over 350,000 tweets are sent, Google gets 3.8million queries, and 243,000 pictures are uploaded on Facebook. The data generated in the last two years has never been generated in world history combined – and a large chunk of this is available on the Internet.

As a researcher in search of data, the Internet has proven to be one of the major sources that could be of help to you.  However, most websites would not hand over data available on their platform to you.

In most cases, you will have to extract them, and in the process, you can even be blocked from doing so. Interestingly, there is hardly any website on the Internet that can protect its content from scraping 100 percent.

With the right skill or leverage at your disposal, you can extract any data you like, provided it is publicly available on the Internet. In this article, I will be showing you how to extract data from the Internet. Before that, let take a look at the idea behind web data extraction.


Web Scraping and Web Data Extraction

Manual data extraction from web pages can be tiring, time-wasting, error-prone, and impossible depending on the size of the data you are interested in. for this reason, web data extraction is done in an automated manner.

The automated means of collecting web data from web pages is web scraping. Web scraping is the use of computer programs known as web scrapers to extract data from web pages. These web scrapers are a form of web bots and have become one of the most important tools for researchers interested in web data. Web Data Extraction Web scraping has made the process of collecting web data easy and very fast. Some web scrapers can send as many as 10,000 web requests in a minute. Web scrapers were introduced as web administrators have refused to hand over data on their websites, put a price tag before providing data they have, or provide a limited data extraction. With a web scraper, even without contact the admin of a website, you can extract the publicly available web data you require – and even do so unnoticed.


Is Web Data Extraction Illegal?

In the past, there has been a lot of argument whether web scraping is legal or not – and many sites will threaten web scrapers with a cease and desist letter. However, in 2019, LinkedIn approached a US court request it to prevent HiQ from scraping its content – and the court refused because the data being scraped is publicly available.

From this time on, it became completely clear that web scraping is not illegal, and you are within the confines of the law provided the data is not copyrighted, and authentication is not required in other to access the data. 

It is also important you know that most illegalities surrounding web scraping stem from the commercialization of the data. I am not a lawyer and not providing you legal service, and as such, I will advise you to seek the advice of a lawyer before you go ahead.


Ways to Extract Web Data

When it comes to extracting publicly available data on the Internet, there are a good number of options available depending on your technical skillset and personal preference or convenience. Below are some of the methods you can use to extract data from web pages.


  • Code a Web Scraper with Python

web scraper programming codes The number one way of extracting data from web pages is by creating your own web scraper. It might interest you to know that all other methods described after these all utilize web scrapers.

The most important prerequisite for coding a web scraper is that you should have coding skills. Web scrapers are computer programs – and you need to write programming codes to develop them. Interestingly, any general-purpose programming language can be used for coding a web scraper, including the likes of Java, JavaScript, C, C#, and PHP, among other general-purpose programming languages you can use to develop web scrapers.

However, for most beginners, the Python programming language is the preferred choice because of the simplicity of the language and clean syntax that makes it easy for beginners – there is also a vast number of libraries and frameworks for developing web scrapers and crawlers. If you have a skill in any of the aforementioned programming languages, then developing a web scraper for extracting data off web pages shouldn’t be a difficult task. There are basically 3 tasks required in web scraping – sending web requests, parsing responses, storing or using the scraped data.

  • Sending web requests

Sending web requests The first task you must take care of is sending HTTP requests to a web server, requesting for a web page on its platform. This requires a higher-level networking skill, and in most programming languages, there are libraries that have been developed to abstract away the complexities and provide you a simple to use API. Take, for instance, with Requests, python programmers only need to write a line of code to get the content of a web page downloaded.

  • Parsing Response

Parsing Response with BeautifulSoup Usually, when a response is sent from a server, it is returned in an HTML document. It is the browsers we use that render them and present them in the form we see them. As a web scraper, you are not interested in rendering but in pulling out data.

If you are dealing with a static page, all of the data will be returned in a go. You will have to extract the required data point and disregard every other content. While Regular Expression can be used, it is difficult to learn, master, and use. for these reasons, developers lookout for a document parsing library. Python developers can make use of BeautifulSoup for traversing DOM and extracting data.

  • Storing Data

Depending on what you require data for, you can either save it in a database (SQLite, MySQL, etc.) or as just a file (CSV or txt). In some cases, you will have to process the collected data and use them in making decisions in your program.

It is important I stress here that websites would not allow you to scrape data without putting up a fight. Almost all popular web services make use of anti-bot techniques to make it difficult for bots to access their content.

Your success as a web scraper is possible only if you are able to circumvent these techniques. The most popular anti-bot techniques include IP tracking and the use of Captchas. With the help of proxies and Captcha solvers, you will be able to circumvent them. Bear in mind that aside from these two, you can be faced with many other challenges.


  • Use a Data Service

The most convenient way of extracting data from websites online is by making use of a data service. There are some web service providers that deal with the provision of data to businesses and researchers. Under the hood, these service providers make use of web scrapers to help you collect data you have an interest in.

If you do not have programming skills or not a technical person, then making use of a data service is the best option out there for you. There are a good number of web data services out there that can provide you contact details, research data, and other forms of data publicly available on the Internet. Let take a look at two of these services briefly.

Scrapinghub Data Service Scrapinghub has strategically placed itself as a web data extraction company as they provide both paid and free tools for web scraping. Interestingly, if you do not want to use their tool, you can opt-in for their data service—currently, Scrapinghub data powers over 2000 businesses. With them, you can get web data delivered to you in the exact way you want it. From Scrapinghub, you can collect data for pricing intelligence, market research, alternative data for investment decisions, content monitoring, and even build data-driven products.

With over 10 years of experience in the business of web scraping, you are sure to get only a team of competent web scrapers to handle your job. Interestingly, they are legally compliant.  The starting price for Scrapinghub data service is $450.

Octoparse Managed Data Service The team behind Octoparse web copywriting captured the description of what they do nicely - If SaaS is not your thing, no worries. We‘ve got you covered. Octoparse is known for providing visual scraping tool.

However, if you are not interested in extracting data yourself, they could help you do that for a fee. Octoparse has served a good number of industries and can provide you hassle-free access to high-quality data. They are flexible, scalable, and provide you formatted and cleaned data ready for further analyses.


  • Make Use of Visual Web Scrapers

Visual Web Scrapers There are some web scrapers that have been developed for use by non-technical users. With a visual web scraper, you do not need to write a single line of code to be able to scrape data from any webpage. All that is required for you is to train the visual web scraper to recognize the data you want – some of the web scrapers can even detect important data points on a page automatically using machine learning. They are available as either installable software or a cloud-based service. There are a good number of them, including both free and paid. However, the free ones come with limitations and as such, going for the paid ones is the best option.

In the past, we have written articles on web scrapers for non-programmers. You can read about our recommendation on the best web scrapers out there here. If you are looking for a free web scraper, you can also read this article for recommendations. ScrapeStorm, ParseHub, and Octoparse are some of the web scrapers out there for you to make use of. One thing you will come to like about these tools is that they are easy to use. A typically visual web scraper will provide you a point-and-click interface for pinpointing some of the data points in other to train the system to help scrape the others you didn’t select but have interest in.


  • Use Excel for Web Data Extraction

How to extract data from a website to excel?

This method of extracting data might come as a surprise to you. You are aware that Microsoft Excel software is a perfect solution for data manipulation and analysis. However, you never knew you could use it for scraping data. Yes, you heard that; Excel has support for web scraping. In just a few mouse clicks, you can scrape web data available on the Internet.

One of the advantages you get from making use of Excel for web scraping is that you avoid paying a dime either for a tool or service of a provider – I assume you already have Excel installed. Excel for Web Data Extraction However, you need to know that while you can use it to extract data from web pages, they are only suitable for extracting tables. For this reason, they might not be the tool for you.

But if the data you are interested in is available in a tabular format online, then the easiest way to extract the data is by making use of Excel. As stated earlier, using Excel for web data extraction is very easy. 

Conclusion

From the above, you can see that there are a good number of options available to you depending on your skillset and personal preference. You no longer have any valid excuse why you have not extracted the data you have an interest in.

As a programmer, you can create your own web scraper for extracting data from web pages. If you do not have coding knowledge, you can either make use of an already-made web scraper or make use of a data service. However, while you go about scraping publicly available data, you need to put into consideration the legal implication.

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