Is Beautiful soup slow?

Beautiful Soup is one of the most popular Python libraries for web scraping. It allows you to easily parse HTML and XML documents to extract data. However, some users have noticed that Beautiful Soup can feel slow when scraping large websites.

The good news is that there are several ways to optimize Beautiful Soup to scrape faster:

Use a Parser That Fits Your Data

Beautiful Soup supports multiple parsers like lxml, html5lib, and Python's built-in html.parser. The default is lxml which provides good balance between speed and accuracy.

However, lxml can use significant memory to parse large docs. So for memory-constrained environments, try html5lib or Python's html.parser.

Parse Only What You Need

Don't parse the entire document if you only need a small portion. Use Beautiful Soup's methods like find(), find_all(), select(), etc to extract only the data you need. This avoids wasting time parsing irrelevant data.

# Only extract table data instead of full HTML
tables = soup.find_all('table') 

Use Caching

Caching stores a local copy of remote web pages to avoid fetching same pages repeatedly. The cache can be reused in future runs for speed.

Popular caching libraries like cachecontrol integrate smoothly with common frameworks like requests.

Monitor Performance

Profile your code with libraries like cProfile to identify bottlenecks. Then optimize just those slow parts instead of prematurely optimizing everywhere.

Beautiful Soup is quite fast out of the box for most use cases. But with some targeted optimizations, you can extract data even faster.