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Clay GTM guide

What is web scraping? How it works, methods, and uses

Web scraping is the automated extraction of data from websites. A program loads a page, reads its underlying HTML, and pulls specific values into a structured format like a spreadsheet or database.

9 min read

Web scraping turns unstructured pages into organized data you can filter, analyze, and act on. Prices, names, addresses, job posts, and other public details become rows, columns, or JSON instead of information trapped inside a browser page.

The web is the largest dataset your team has, and almost none of it arrives in a usable shape. Scraping closes that gap. It converts pages built for human eyes into data a machine can sort. This guide covers how scraping works, the main methods, the GTM use cases that matter, responsible scraping practices, and how AI is changing the process.

How does web scraping work?

Every web scrape follows the same loop, no matter which tool runs it. Understanding the loop makes every scraping tool easier to reason about.

The four steps of every web scrape

01

GET /page → HTML

02

Document tree

03

Target fields

04

Clean data row

Request

The scraper sends an HTTP request and the server returns the page's raw HTML.

Every web scrape is the same four-step loop: request the page, parse its HTML, extract the target values, and structure them into rows.

The hard part is almost never the request. It is the extract step. A page's layout does not tell a scraper which tag holds the price and which holds a footer link. Traditional scrapers depend on exact selectors. Change the page and the scrape can break. AI-based scraping reduces that fragility by reading the page for meaning instead of relying only on its markup.

Methods of web scraping: HTML parsing, headless browsers, and APIs

There are three core ways to get data off a page. They differ by how much of the page they need to load first. Pick the lightest method that still returns the data you need.

Three methods, from lightest to heaviest

MethodHow it worksBest forMain limitation
HTML parsingFetch the raw HTML and read values from the document structureStatic, table-like pages that load content on the first requestBreaks when the layout changes or content loads with JavaScript
Headless browsersRun a real browser without a screen, execute JavaScript, then read the rendered pageDynamic sites, content behind clicks or scrolls, and single-page appsSlower, heavier, and more likely to trigger anti-bot checks
Official APIsRequest clean data directly from a published endpointSites that offer an API and permit programmatic accessRate limits, access keys, and incomplete field coverage

An official API is the cleanest option when it exists because the site provides structured data intentionally. HTML parsing is the fastest option for simple pages. Headless browsers are the fallback when a page will not expose its data until JavaScript runs.

What does scraped data look like? From HTML to structured rows

The output is the point of the whole exercise. The input is a page written for a browser. The output is a set of fields you can query.

Same listing, before and after extraction

Raw HTML from one business listing

<div class="listing"><h2 class="name">Bright Spark Electric</h2>

<span class="tel">(212) 555-0148</span><p class="addr">New York, NY</p>

<div class="stars" data-rating="4.8"></div></div>

Structured fields

Scraping turns an unstructured web page into structured fields you can sort, filter, and act on.

Once the data sits in rows, it stops being a web page and becomes a working dataset. You can deduplicate it, score it, join it to your CRM, or push it into an outreach sequence. Most scraping outputs land as CSV, JSON, or columns in a table.

What is web scraping used for?

Scraping earns its place when the data you need is public but scattered across pages no vendor packages for sale. That describes much of what a go-to-market team wants.

Four common web scraping use cases

Source pages

Business directories and local listings

Fields extracted

CompanyWebsitePhoneCategory

Payoff

Build targeted prospect lists that off-the-shelf databases miss.

Each recurring GTM job is a different public source page turned into a different set of structured fields.

Lead lists are a common driver. Small and local businesses can be hard to find in traditional B2B databases, so public listings may be the most accurate source. Regency Supply used public map listings to find and monitor thousands of niche contractor contacts.

5,000+

Key contractor contacts Regency Supply found and monitored after automating public-listing research in Clay.

Read the full story

The other jobs follow the same shape. Market research reads competitor and review pages to see what rivals ship and hire for. Pricing intelligence watches published prices over time. GTM enrichment pulls facts from company sites and public filings that no standard provider exposes as a ready-made field.

Scraping publicly available data is broadly permitted in the United States, but the answer depends on the jurisdiction, the site's rules, the data collected, and how the collection is performed. This is general information, not legal advice.

Two boundaries matter most. Data behind a login, paywall, or password carries more legal and account risk than open public data. Personal data can trigger privacy obligations such as GDPR in Europe and CCPA in California, whether it was scraped or purchased.

Best practices for responsible scraping

Do thisWhy it matters
Check the site's terms of service and robots.txtThey communicate the owner's access rules and preferences
Scrape public data, not content behind logins or paywallsGated data carries higher legal and account risk
Rate-limit requestsExcessive traffic can disrupt the site and get your scraper blocked
Handle personal data carefullyPrivacy laws apply regardless of how personal data was obtained
Use an official API when one existsIt is the sanctioned and usually more stable route

How AI is changing web scraping

Traditional scraping is brittle by design. You tell the scraper the exact tag that holds each value, and the scrape survives only until the site changes its layout. AI scraping removes much of that dependency. An AI agent reads the rendered page for meaning, then returns the fields you requested in plain language.

The shift is from writing selectors to writing instructions. Instead of finding an element with a class like price-tag, you can ask for the company's pricing or the words not listed when none appears. Clay's AI research agent, Claygent, visits a page, reads it, and returns structured fields on request.

A-LIGN replaced a manual research process that had run through 2,000 accounts. Its first automated workflow delivered more useful data at lower cost and higher speed.

15x

More useful information from A-LIGN's automated research workflow than the manual process it replaced.

Read the full story

Here is the kind of instruction that drives AI extraction. Describe the fields once and run it across every row in a table.

AI web research prompt
You are researching a company. Visit {{company website}} and return:- what the company sells (one sentence)- their primary customer type (SMB, mid-market, or enterprise)- any pricing shown on the site, or "not listed"- the city of their headquartersReturn each field in its own column. If a field is not found, return "unknown". Do not guess.

How to scrape web data with Clay, no code

Clay turns scraping into a step inside a data workflow instead of a standalone script. You scrape a page, and the result lands as columns beside the rest of your data, ready to enrich, score, and sync. The right tool depends on the page.

Pick the right Clay tool for what you're scraping

1

What are you scraping?

A practical default is to start with Claygent for open-web research. Use Zenrows when the page is protected or heavily dependent on JavaScript. Use an Apify actor for bulk collection from a specialized source. The native scraper is the low-cost choice for simple pages, and the Chrome extension captures lists already visible in your browser.

Once the scraped data is in a Clay table, it behaves like any other column. You can validate it, run it through an enrichment waterfall, and sync it to your CRM. The workflow can combine scraped public facts with provider data instead of leaving them in separate tools.

Coverflex uses AI research and enrichment to prioritize a market that no packaged database covers cleanly across Portugal, Spain, and Italy.

3M+

Companies in Coverflex's signal-based outreach market, researched and prioritized with Clay.

Read the full story

Outcomes from web research workflows in Clay

CompanyOutcomeStory
Regency Supply5,000+ niche contractor contacts found and monitoredRead
A-LIGN$5.7M in qualified pipeline from automated account researchRead
Coverflex3M+ companies in its signal-based outreach marketRead

Scrape and structure web data without code

Use Claygent and Clay's scraping tools to turn public pages into clean, enriched records your GTM team can act on.

Frequently asked questions

Is web scraping legal?

Scraping publicly available data is broadly permitted in the United States, but legality depends on the jurisdiction, the site's terms, the data, and how it is collected. Risk rises when data is behind a login or paywall or includes personal information regulated by laws such as GDPR or CCPA. Check the site's terms and robots.txt and seek legal advice for sensitive projects.

What is web scraping used for?

For GTM teams, common uses include building lead lists from public directories, researching competitors and markets, monitoring published pricing, and enriching CRM records with facts from company sites and public filings. It is most valuable when the data is public but no vendor sells it as a clean field.

What is the difference between web scraping and web crawling?

Crawling is discovery: a bot follows links to find and index pages. Scraping is extraction: pulling specific values from the pages you already know about. A large project may crawl to build a URL list, then scrape each URL for the required fields.

Do you need to know how to code to scrape a website?

No. Writing a scraper in Python or JavaScript gives you control, but no-code tools cover many common jobs. In Clay, the native scraper, Chrome extension, Zenrows, Apify actors, and Claygent can capture pages and return fields without writing selectors or scripts.

What is the difference between web scraping and using an API?

An API is a structured endpoint the site publishes for programmatic use. Scraping reads the human-facing page and extracts values that may not be exposed through an API. Use an official API when it provides the fields you need, and scrape public pages when no suitable API exists.