How web scraping works
Web scraping starts with a URL and ends with structured records. A typical scraper follows four steps:
- Fetch the page. An HTTP client requests the URL and receives HTML or JSON.
- Render dynamic content. Pages that load data in the browser may need a headless browser to run their JavaScript.
- Extract fields. CSS selectors or XPath expressions locate elements such as names, prices and links.
- Clean and store results. The scraper validates values and writes them to CSV, JSON or a database.
Scrapers should also record the source URL and collection time so changes can be traced.
Web scraping vs web crawling
A web crawler discovers and follows links. A scraper extracts chosen data from the pages it receives.
| Web scraping | Web crawling | |
|---|---|---|
| Goal | Extract specific data | Discover URLs |
| Output | Structured records | URL list or index |
| Typical scope | Selected pages | Many linked pages |
One system may do both: the crawler finds product pages, then the scraper collects each product’s price and availability.
Common uses
- Tracking product prices, stock and promotions across markets.
- Collecting listings or reviews for market research.
- Recording localized search results for SEO analysis.
- Checking ads, redirects and landing pages by location.
How to scrape responsibly
- Check access rules. Review the site’s terms and robots.txt before collecting data.
- Prefer supported access. Use an official API when it provides the data you need.
- Control request volume. Set concurrency limits, add delays and back off after rate limiting or a 429 response.
- Protect data. Don’t collect private, sensitive or copyrighted material without a valid basis and permission where required.
A rotating proxy spreads requests across exit IPs, but it doesn’t fix excessive traffic, inconsistent headers or browser fingerprints. Stay within the site’s limits rather than treating rotation as permission to ignore them.
Web scraping with FlashIP
FlashIP rotating residential proxies use ethically sourced residential IPs: real home IPs from genuine ISP networks. Request mode rotates the exit IP for every request, while sticky sessions keep it for 30, 60, 90 or 120 minutes. Country, state, city and ASN targeting supports location-specific collection, and traffic is sold in one-off per-GB packages; see residential pricing.
FAQ
Is web scraping legal?
It depends on the jurisdiction, data, access method and intended use. Review the site’s terms, privacy rules, copyright restrictions and applicable laws before starting.
Do I need a proxy for web scraping?
No. A small, permitted job may work from your normal connection. Proxies are useful for location-specific data and distributed collection, but they don’t replace rate controls or permission.
Can web scraping handle JavaScript websites?
Yes, but an HTML-only client may not see content loaded after the page opens. Use a browser automation tool when JavaScript must run, or use an authorized data endpoint when the site provides one.