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What is web scraping? A complete guide.

Web scraping is the process of extracting data from websites. It's used for lots of practical applications, from academic research to market analysis. The rapid collection of web data means that scraping tools can give valuable insights into trends, prices, and sentiment.

What is web scraping: diagram showing data going from website through scraping platform to structured data

What is web scraping?

Web scraping is the process of automatically collecting large amounts of data from websites. It involves accessing a web page, interpreting the data, and extracting the required information.

You could do this manually by copying and pasting, but scraping is typically performed using an automated tool that can pull data from web pages. Web scraping is also known as web harvesting and web data extraction.

What is web scraping? Learn all about web scraping and its use cases in our YouTube video!

What is the definition of web scraping?

Web scraping can be defined as the automated process of extracting data from a website. It involves retrieving a site's HTML code, then examining that code to pull out specific data such as text, images, or prices. This technique enables the rapid collection and organization of web data.

What's the point of web scraping?

It's already impossible for us humans to process even a fraction of the data on the web. That's why web scraping is becoming essential. We need machines to rapidly read that data for us so that we can use it in new and interesting ways.

To illustrate, imagine how long it might take you to manually copy and paste text from 100 web pages. A machine could do it in less than a second if you give it the correct instructions. It can also do it repeatedly, tirelessly, and at any scale.

Forget about 100 pages. A computer could deal with 1 million pages in the time it would take you to open just the first few!

Web scraping can be used for everything from academic research to business intelligence. It's used to gather data at scale on product prices, weather information, market trends, and much more.

What is web scraping? What is web scraping? Globe with the words web scraping surrounded by forms of data

Web scraping means extracting data from all over the World Wide Web.

How do web scrapers work?

Web scrapers operate by sending HTTP requests to a web server, the same way that a browser would when you visit a site. Once the server responds with the page's HTML code, the scraper parses this code to locate particular HTML tags, classes, or attributes that contain the data to be scraped.

After extraction, data manipulation can transform it into a structured format, like a CSV file or database. Web scrapers can extract data from multiple web pages at a time, making them great for large-scale data mining.

What is web scraping? Structured data from web scraping.

Structured data is the ultimate goal of web scraping unstructured data from the web.

What is scraping data?

Scraping data refers to the process of extracting specific information from web pages or other online sources. It involves sending requests to the target website, retrieving the HTML code, and then parsing that code to locate and extract information.

This unstructured data might include text, images, prices, contact details, or any other information publicly displayed on a web page. The scraped data is often cleaned, turned into structured data, and stored in a database or file for further analysis or use. Structured data is just a way to say that the information is easy for computers to read.

What is web data extraction?

Web data extraction expands on the concept of data scraping by not only retrieving information but also transforming and organizing it into a more usable format. While scraping is the act of pulling data from web pages, extraction involves additional steps to ensure that the data extracted is ready for analysis or integration into applications in a structured format.

This can include cleaning the data to remove unnecessary characters or formatting, converting it into a specific structure like a CSV file or Excel spreadsheet, and even performing initial analyses to derive insights. Web data extraction is a crucial component in data-driven processes, enabling businesses, researchers, and developers to transform raw scraped data into information that can inform decision-making.

Web scraping is used to extract what type of data?

Web scraping can be used to extract a wide variety of data types from the internet. It can gather textual information such as product descriptions, prices, contact details, and customer reviews, as well as visual content like images and videos. Depending on the use case, you can target specific data such as real estate listings, stock market trends, job postings, market research, or travel fares. It's also used for lead generation, to collect sentiment data from social media, news articles for content aggregation, content scraping by the media, and scientific data for academic research.

What is web scraping? Image of futuristic computer with data.

Scraped data provides insights and information for businesses, academic research, and a wide range of other fields.

What is web scraping used for?

Lead generation

Web scraping is used to gather contact information and details about potential customers from various online platforms. By collecting data from websites like LinkedIn, businesses can identify and target specific demographics. This kind of contact scraping can generate better leads.

Market research

Understanding market dynamics is crucial for any business. Web scraping allows analysts and researchers to collect vast amounts of data from various sources. This information, which might include customer reviews, competitor strategies, or market trends, helps to build a comprehensive picture of the industry landscape and enables brand monitoring.

Price monitoring and competitive intelligence

Price monitoring involves tracking the fluctuations in the prices of goods or services over time. It lets businesses keep an eye on these changes, allowing them to adapt their pricing models and strategies.

Competitive intelligence takes the concept of price monitoring a step further by employing advanced analytics and insights gathered through price scraping. Combining competitor analysis with market trends, customer behavior, and other influencing factors, can lead to a more nuanced and strategic approach to pricing.

Real estate listing scraping

In the real estate industry, web scraping is employed to gather detailed information about properties listed online. This can include everything from location and price to features and photos. By consolidating this data, real estate professionals can offer more tailored online services to their clients and stay ahead of market trends.

Sentiment analysis

Web scraping plays a vital role in sentiment analysis by gathering opinions, reviews, and comments from social media, forums, and review sites. Market research companies can analyze this data to gauge public sentiment about products, services, or brand image, enabling them to respond to customer needs and preferences effectively.

Job market analysis

Recruitment agencies and HR professionals can make use of web scraping to monitor job postings on sites like Indeed. By analyzing job descriptions, salary trends, and skill requirements, they can gain insights into labor market dynamics, helping both employers and job seekers.

Academic research

Researchers and academics can use web scraping to collect data from publicly available sources for scientific studies and analyses. This can include information on climate patterns, historical documents, social behavior, or data for generative AI or machine learning.

Travel fare aggregators

Travel aggregators and comparison sites use web scraping to gather information on flight fares, hotel prices, and vacation packages from various providers. This enables them to offer customers an overview of available options and pricing.

News and content aggregation

Web scraping enables media companies and news aggregators to collect articles, blogs, and news stories from different sources. This content scraping assists in creating centralized platforms where users can access diverse content from various publishers.

Stock market analysis

Investors and financial analysts use web scraping to track stock prices, market news, and financial reports. By continuously monitoring relevant data, they can identify trends, make predictions, and formulate investment strategies aligned with market movements.

Healthcare data extraction

In the healthcare sector, web scraping can be used to collect data on disease outbreaks, medical research, patient reviews, and more. This information can support public health initiatives, medical studies, and healthcare service improvements. Scraping was used extensively during the COVID-19 pandemic.

Comparison websites

Comparison websites are a great example of how web scraping can benefit consumers. These platforms use web scraping to extract data on products or services from online retailers and service providers. Aggregating information such as prices, features, customer reviews, and availability, lets these websites present users with a side-by-side view of their options.

What are the benefits of web scraping?

Web scraping offers lots benefits and giving anyone the means to access and analyze vast amounts of data from the web. But here are pros and cons, so you should be aware of those.

At the end of the day, automating the data collection process, means that web scrapers save time and resources, and make it easier and faster to make decisions or think strategically.

What is web scraping? Illustration of data points on the web.

Web scraping is all about extracting data from across the web.

What is the difference between a web crawler and a web scraper?

Web crawlers and web scrapers serve different functions. A web crawler, also known as a spider or bot, systematically browses the internet to index web pages. Its core purpose is to discover and navigate websites. Web crawling is often used by search engines to update their indexes.

On the other hand, a web scraper is designed to extract specific information from web pages. While a crawler moves through sites to find pages, a web scraper focuses on pulling data from those pages.

Web scraping is sometimes thought to be the same as screen scraping, but there are differences.

What is web scraping with Python?

Web scraping with Python uses the Python programming language to gather data from websites. Python is a popular choice for web scraping because of its simplicity and a rich ecosystem of libraries like Beautiful Soup, Scrapy, and Selenium. These libraries provide functions to send HTTP requests and navigate HTML code.

Is web scraping easy?

That depends on the complexity of the website being scraped. For simple data extraction from a website with a clear and consistent structure, scraping can be relatively straightforward, especially with the aid of various tools and libraries designed to facilitate the process.

Scraping more complex sites that use dynamic content loading, anti-scraping measures, or intricate HTML structures can be challenging even for experienced developers.

How do I extract data from a web page?

The scraping process involves a number of steps:

  1. Identify the URL(s): Determine the web page(s) containing the data you want to extract.

  2. Send a request: Use tools or code to send an HTTP request to the identified URL.

  3. Parse the HTML: Use parsing methods to navigate through the HTML code of the page.

  4. Extract the data: Locate and retrieve the specific information needed from the HTML.

  5. Clean and structure: Process the extracted data into a usable structured format, such as an Excel spreadsheet or database.

Web scraping depends on various tools and programming languages, including Python, JavaScript, and specialized scraping software to carry out these steps.

What is an example of scraping?

Imagine an online electronics retailer scraping information from rival websites. The retailer extracts data on pricing, features, and customer reviews. The price scraping might reveal that competitors are pricing certain items lower or offering unique bundles.

And by analyzing customer reviews and ratings, the retailer can gain insights into what customers value most and what areas might need improvement.

The retailer can then adjust their pricing strategy, introduce similar bundles, or explore new market opportunities. This ongoing strategy helps them stay competitive, respond to market changes, and better understand customer preferences.

What is web scraping? Illustration of wall of data.

Much of the data on the web is like a wall of indistinguishable noise. Web scraping aims to extract and organize that data.

Is web scraping legal?

Yes, web scraping is legal, but the legality of extracting data from a website can depend on the website's terms of service, the nature of the scraped content, and how the scraping is conducted. If you're worried, please read our extensive blog post on the legality of web scraping.

Can websites tell if you scrape them?

Yes, website owners can detect web scrapers. Activity like rapid, repeated requests from the same IP address or behavior that doesn't align with typical human browsing can trigger alarms. Many websites use anti-scraping measures such as CAPTCHAs or block IP addresses to block scrapers.

Can you get banned for web scraping?

Yes, you can get banned if you violate a website's terms of use or engage in activities that the site considers abusive. Bans may involve IP blocking, account suspension, or other measures to prevent further access.

What is web scraping? Illustration of robots extracting data.

Web scraping robots may not look like this in real life, but they are busily extracting data all day every day all over the world.

What are some good web scraping tools?

If you're a developer, libraries like Beautiful Soup and Scrapy in Python offer flexibility and power. Apify is another strong option, with both ready-made web scraping tools and a mature platform for custom scraper development. Apify also supports and maintains Crawlee, a modern open-source web scraping library. For the less technical, tools like Octoparse and ParseHub provide intuitive graphical interfaces to scrape data without writing code. Selenium, Playwright, and Puppeteer are popular tools that are especially useful for handling dynamic content loaded via JavaScript. The future of web scraping is also being affected by the rise of AI web scraping tools.

Are browser extension web scrapers as good as dedicated scraping tools?

Browser extensions allow users to scrape data directly from the browser. They're user-friendly and are good for simple, small-scale tasks.

Dedicated scraping tools and web scraping software are designed with more complex tasks in mind. They're more flexible, can handle large volumes of data, and often come with features like proxy management and CAPTCHA solving.

Should you build your own web scraper or use a pre-built scraper?

Writing your own web scraping code gives you complete control over its functionality. If you have unique requirements or need to scrape websites with unique HTML site structures, building your own might be the way to go. But it will need significant technical expertise and can take a long time.

Using a ready-made scraper gives you a quicker and more user-friendly way to get started. A pre-built scraping tool will also often include built-in features to handle common scraping challenges.

Should you run your scraper on the cloud or locally?

Running a scraper locally means that it operates on your personal computer or server. This gives you direct control and might be simpler to set up, but it may limit scalability.

Cloud-based scraping means easy scaling, better reliability and speed, and often includes advanced features like proxies, IP rotation, monitoring, API access, and distributed scraping bots. Local scraping suits smaller projects, but cloud scraping is better for large-scale scraping or long-running tasks.

Want to start web scraping?

Visit Apify Store if you just want to use a pre-built scraper. You can find scrapers there for e-commerce websites, lead generation, and more. If you can't find what you need, you can request a web scraper from our certified Apify partners.

And if you're ready to build your own web scrapers, check out our Web Scraping Academy.

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