Here is a 2220 word guide on using VBA for web scraping in Excel:
Introduction to VBA Web Scraping
Web scraping is the process of extracting data from websites and saving it structured formats like Excel. VBA (Visual Basic for Applications) is a programming language developed by Microsoft that allows automation of tasks across Office applications. By combining VBA with Excel, you can write scripts to scrape data from web pages and automatically load it into spreadsheets for analysis and reporting.
Some key advantages of using VBA for web scraping include:
- VBA comes bundled with Excel so you don‘t need to install additional libraries or dependencies to start scraping. Just enable the developer tools in Excel and you‘re ready to go.
- The tight integration between VBA and Excel makes it easy to transfer scraped data between the code and spreadsheet. You can directly output values into cells and ranges.
- VBA has built-in support for browser automation through the Internet Explorer object model. This provides an easy way to load pages, click elements, and extract data.
- VBA web scrapers can be packaged alongside an Excel workbook and distributed to end users. The macro can scrape fresh data with a single click without requiring programming knowledge.
Of course, VBA also has some downsides compared to more modern tools like Python:
- VBA has a steeper learning curve than Python and other beginner-friendly languages. The syntax can be a bit complex for coding newcomers.
- Browser automation relies on Internet Explorer which is legacy technology at this point. Support for modern browsers is limited.
Overall VBA scraping is a great fit when you need a Windows-based scraper that outputs data directly into Excel. It eliminates the hassle of exporting scraped data from an external tool into Excel separately. The learning curve is steeper than other languages but once mastered, the tightly coupled Excel-VBA workflow produces an easy-to-use scraper.
Setting up the VBA Environment
Before writing any scraping code, you first need to activate the developer tools in Excel and add references to gain HTML parsing and Internet capabilities. Here are the steps:
- Open your Excel workbook and navigate to File > Options > Customize Ribbon. Check the ‘Developer‘ box and click OK. This will enable the Developer tab on the ribbon.
- Click the Developer tab and select Visual Basic to open the VBA editor.
- Inside the VBA editor, click Tools > References to open the library reference manager.
- Scroll down and check the boxes for "Microsoft HTML Object Library" and "Microsoft Internet Controls". Click OK.
Those two libraries add the core objects and methods like HTMLDocument and InternetExplorer that allow VBA to interact with web pages. Now you can start coding your web scraper!
Navigating to Web Pages
The first step in any web scraping script is navigating to the target URL that you want to extract data from. Here is sample code to open a web page:
Sub WebScraper() Dim IE As New InternetExplorer ‘Create IE browser object IE.Visible = True ‘Make it visible IE.Navigate "https://example.com" ‘Navigate to URL While IE.ReadyState <> 4 ‘Wait for page to load DoEvents Wend ‘Remaining scraping code goes here End Sub
- The InternetExplorer object represents an instance of Internet Explorer that we can control via code.
- Setting Visible to True makes the browser UI visible on screen while scraping. Setting to False hides it.
- The Navigate method goes to the specified URL.
- The loop waits for the ReadyState to equal 4, which means the page has finished loading.
- DoEvents keeps Excel responsive since the loop halts VBA execution until the page loads.
Now that we can reliably load web pages, it‘s time to start extracting data!
Basic Web Scraping Techniques
The webpage content lives in an HTMLDocument object that can be parsed to scrape data. Here are some common methods:
- QuerySelector – Finds the first element matching a CSS selector
- getElementsByTagName – Gets all elements by tag name
- getElementById – Gets a single element by its ID
- getElementsByClassName – Gets all elements matching a class name
For example, to scrape all paragraph text from a site:
Dim doc As HTMLDocument Set doc = IE.document Dim paras As Object Set paras = doc.getElementsByTagName("p") For Each p In paras MsgBox p.innerText Next p
We can combine these methods with loops and conditionals to extract exactly the data we need:
‘Get product data from ecommerce site Dim products As Object, product As Object Set products = doc.getElementsByClassName("product") For Each product In products Dim name = product.getElementsByClassName("name")(0).innerText Dim price = product.getElementsByClassName("price")(0).innerText ‘Save data to Excel here MsgBox name & " - " & price Next product
This loops through each product, extracts the name and price, and could save it to the spreadsheet using Range/Cells. The key is drilling down and targeting the exact elements that contain the data you want.
Handling Dynamic Website Content
‘Click "Load More" button to reveal additional data Dim loadMore As Object Set loadMore = doc.getElementById("loadMore") Do While loadMore IsNot Nothing loadMore.Click ‘Wait for new content to load Set loadMore = doc.getElementById("loadMore") Loop ‘Extract updated page content
This simulates a human user clicking the button until no more content loads.
Dim xmlhttp As Object Set xmlhttp = CreateObject("MSXML2.XMLHTTP") xmlhttp.Open "GET", "https://api.example.com/data", False xmlhttp.Send Dim ajaxResults As String = xmlhttp.ResponseText ‘Parse ajaxResults JSON/HTML here
This scrapes the endpoint without needing to simulate browser actions.
Storing Scraped Data in Excel
A major benefit of VBA web scraping is the built-in support for dumping data directly into Excel. Here are some ways to output results:
- Write to individual cells:
Cells(2, 1).Value = "Name" Cells(2, 2).Value = scrapedName
- Write arrays to ranges:
Dim results(2,2) As String results(0,0) = "Product" results(0,1) = "Price" results(1,0) = scrapedProduct results(1,1) = scrapedPrice Range("A2").Resize(UBound(results, 1)+1, UBound(results, 2)+1).Value = results
- Loop through results:
Dim rowCounter As Long For Each product In products rowCounter = rowCounter + 1 Cells(rowCounter, 1).Value = product.name Cells(rowCounter, 2).Value = product.description Next product
This writes the scraped data to cells and ranges, dynamically expanding as needed.
With the data in Excel, you can then use formulas, pivots, and charts for further analysis.
Debugging and Troubleshooting VBA Web Scraping Scripts
As with any code, you‘ll eventually run into bugs and errors when writing a VBA web scraper. Here are some tips for debugging and troubleshooting:
- Set breakpoints to pause execution at specific lines. When paused, hover over variables to inspect their values.
- Use MsgBox and Debug.Print to output messages at key points in the code.
- Handle errors gracefully with On Error statements rather than simple On Error Resume Next.
- If elements can‘t be found, try selecting them manually in the browser to verify the selector.
- Temporarily write scraped data to a text file using FileSystemObject when debugging failed Excel output.
- For HTTP request problems, inspect status codes and response headers.
- Use Firefox/Chrome developer tools to identify dynamically loaded content that needs special handling.
- Try enabling QC (quick compile) in the VBA settings for clearer error messages.
- If browsers are blocked or throttled, rotate User Agents or add delays between requests.
Debugging takes some patience but pays off to build a robust, production-ready scraper.
Advanced Web Scraping Capabilities
While the basics will cover most simple scraping needs, there are several advanced capabilities unlocked by VBA:
Logging into websites
- Find username and password fields by ID, name attribute or tag name
- Set .Value of input fields to credentials
- Locate and click submit button to login
- Create FileSystemObject
- Call .DownloadFile method to download to chosen local folder
Filling out and submitting forms
- Set .Value of each input field
- Select options from dropdowns
- Click submit button
- POST form data directly via XMLHTTPRequest
- Interact with additional browser events like Alert popup
- Extract cookies and pass between sessions
- Scroll web pages by setting scrollbar position
- Route requests through a proxy like the WinHttp object
- Manage cookies at a higher level than the browser
- Mimic headers and settings cross-domain
These give a glimpse into some of the more complex tasks you can perform beyond basic data extraction. The limit is your imagination!
Sample VBA Web Scraping Project
To tie the concepts together, let‘s walk through a sample project scraping hotel listings from TripAdvisor. Here is an overview of the script‘s logic:
- Prompt user for search keywords and number of pages to scrape
- Construct search URL based on keywords and page number
- Loop through each page from 1 to specified max
- Load page HTML into document object
- Extract hotel name, price, review count, rating, location
- Write data to next available Excel row
- Display message when scraping finished
And here is the full code:
Sub TripAdvisorScraper() ‘Collect inputs Dim keywords As String, maxPages As Long keywords = InputBox("Enter desired destination") maxPages = InputBox("Enter max pages to scrape") ‘Initialize variables Dim url As String, page As Long, doc As HTMLDocument Dim rowCounter As Long rowCounter = 2 ‘Start writing data to row 2 ‘Loop through pages For page = 1 To maxPages ‘Construct URL url = "https://www.tripadvisor.com/Hotels-" & keywords & "-Hotels-oa" & page & ".html" ‘Load page Set doc = GetHTMLDoc(url) ‘Find hotels Dim hotels As Object Set hotels = doc.getElementsByClassName("listing") ‘Extract data from each hotel For Each hotel In hotels ‘Hotel name Dim name As String name = hotel.getElementsByClassName("listing_title")(0).innerText ‘Price Dim price As String If hotel.getElementsByClassName("price").Length Then price = hotel.getElementsByClassName("price")(0).innerText Else price = "N/A" End If ‘Review count Dim reviews As String reviews = hotel.getAttribute("data-reviews-count") ‘Rating Dim rating As String rating = hotel.getElementsByClassName("rating")(0).innerText ‘Location Dim location As String location = hotel.getElementsByClassName("location")(0).innerText ‘Write hotel data to Excel Cells(rowCounter, 1).Value = name Cells(rowCounter, 2).Value = price Cells(rowCounter, 3).Value = reviews Cells(rowCounter, 4).Value = rating Cells(rowCounter, 5).Value = location rowCounter = rowCounter + 1 Next hotel Next page MsgBox "Scraping complete!" End Sub ‘Returns HTML document for given URL Function GetHTMLDoc(url As String) As HTMLDocument Dim IE As New InternetExplorer IE.Visible = False ‘Disable UI IE.Navigate url Do While IE.ReadyState <> 4 DoEvents Loop Set GetHTMLDoc = IE.document End Function
This demonstrates core techniques like:
- Prompting for user input
- Concatenating values into a URL
- Looping through pagination
- Extracting multiple attributes from listings
- Writing each result to the next row
- Using a helper function to reduce duplicate code
After running, you‘ll have a spreadsheet populated with hotels, prices and other data ready for further analysis!
Resources for Learning VBA Web Scraping
Here are some recommendations to level up your web scraping skills:
- Microsoft Documentation – Official VBA reference
- Automate The Boring Stuff – Practical programming projects
- Excel Exposure – Courses focused on Excel VBA
- Stack Overflow – Solutions to common VBA questions
- Reddit – Active VBA programming discussions
- YouTube – Video tutorials covering web scraping topics
- Udemy – Paid courses on Excel, VBA and web scraping
Start by mastering the fundamentals covered here, then expand your knowledge. Soon you‘ll be scraping advanced sites and exploring the limits of what‘s possible with VBA web automation!