# PublicWWW > Search engine for source code. It indexes the HTML, JavaScript and CSS of several hundred million sites, so a snippet, a tracking id, a library name or any other string can be traced to the sites that carry it. Typical questions it answers: which sites embed this widget, who still runs that library version, which sites load a given tag manager or analytics script, how many sites carry a particular analytics id. A query is a string to look for in page source. Quote it for an exact phrase; modifiers narrow it down (`site:`, `depth:`). Results are paginated; how many rows are visible depends on the plan. Every documentation page below is Markdown (the same page as html without index.md at the end); the whole documentation in one file: https://publicwww.com/llms-full.txt ## Query Syntax Every operator and modifier for building a query: exact phrases, RegEx, site:, ccTLDs and more. - [Query Syntax](https://publicwww.com/docs/query-syntax/index.md) - [Basics](https://publicwww.com/docs/query-syntax/basics/index.md) - [Operators](https://publicwww.com/docs/query-syntax/operators/index.md) - [Regular expressions](https://publicwww.com/docs/query-syntax/regex/index.md) - [Country domains](https://publicwww.com/docs/query-syntax/cctld/index.md) ## Signatures Find the code a product leaves on its customers' websites, and turn it into a query. - [Signatures](https://publicwww.com/docs/signatures/index.md) - [Where products leave traces](https://publicwww.com/docs/signatures/traces/index.md) - [Checking a signature](https://publicwww.com/docs/signatures/checking/index.md) ## Technologies Ready-made queries for over a thousand technologies, by topic - from ad pixels and analytics to frameworks, shops and payments. - [Technologies](https://publicwww.com/docs/examples/index.md) - [Advertising](https://publicwww.com/docs/examples/ads/index.md) - [Ad pixels & affiliate](https://publicwww.com/docs/examples/pixels/index.md) - [Marketing](https://publicwww.com/docs/examples/marketing/index.md) - [Email & automation](https://publicwww.com/docs/examples/email/index.md) - [Reviews & store apps](https://publicwww.com/docs/examples/reviews/index.md) - [Analytics](https://publicwww.com/docs/examples/analytics/index.md) - [Product analytics, replay & monitoring](https://publicwww.com/docs/examples/product-analytics/index.md) - [A/B testing](https://publicwww.com/docs/examples/ab-testing/index.md) - [Consent & cookie banners](https://publicwww.com/docs/examples/consent/index.md) - [Chat & support](https://publicwww.com/docs/examples/chat/index.md) - [CAPTCHA & bot protection](https://publicwww.com/docs/examples/captcha/index.md) - [Accessibility](https://publicwww.com/docs/examples/accessibility/index.md) - [Hosting & CDN](https://publicwww.com/docs/examples/hosting/index.md) - [Servers & languages](https://publicwww.com/docs/examples/webtech/index.md) - [Library, font & image CDNs](https://publicwww.com/docs/examples/cdn-libs/index.md) - [JavaScript libraries](https://publicwww.com/docs/examples/frontend/index.md) - [CSS frameworks, fonts & icons](https://publicwww.com/docs/examples/css/index.md) - [Sliders & UI components](https://publicwww.com/docs/examples/ui/index.md) - [Animation, charts & maps](https://publicwww.com/docs/examples/charts/index.md) - [JS frameworks](https://publicwww.com/docs/examples/frameworks/index.md) - [Widgets](https://publicwww.com/docs/examples/widgets/index.md) - [CMS](https://publicwww.com/docs/examples/cms/index.md) - [WordPress themes & plugins](https://publicwww.com/docs/examples/wordpress/index.md) - [Headless CMS & static sites](https://publicwww.com/docs/examples/headless/index.md) - [Site builders](https://publicwww.com/docs/examples/site-builders/index.md) - [Shop platforms](https://publicwww.com/docs/examples/ecommerce/index.md) - [Payments](https://publicwww.com/docs/examples/payments/index.md) - [Discontinued, still running](https://publicwww.com/docs/examples/discontinued/index.md) ## Clusters Keep a set of sites, compare it against next month's, and read fields off every site in it. - [Clusters](https://publicwww.com/docs/clusters/index.md) - [Creating a cluster](https://publicwww.com/docs/clusters/creating/index.md) - [Extraction](https://publicwww.com/docs/clusters/extraction/index.md) - [Limits](https://publicwww.com/docs/clusters/limits/index.md) - [Example: tracking a widget change](https://publicwww.com/docs/clusters/example-widgets/index.md) - [Example: extracting phones and emails](https://publicwww.com/docs/clusters/example-contacts/index.md) ## API Search from your own code. JSON, XML, CSV, NDJSON and TSV, with a key and a plan. - [API](https://publicwww.com/docs/api/index.md) - [Authentication](https://publicwww.com/docs/api/authentication/index.md) - [Making requests](https://publicwww.com/docs/api/requests/index.md) - [Response formats](https://publicwww.com/docs/api/formats/index.md) - [Quotas and rate limits](https://publicwww.com/docs/api/limits/index.md) - [Errors](https://publicwww.com/docs/api/errors/index.md) - [Clusters](https://publicwww.com/docs/api/clusters/index.md) - [Code examples](https://publicwww.com/docs/api/examples/index.md) - [Google Sheets](https://publicwww.com/docs/api/sheets/index.md) - [Clay](https://publicwww.com/docs/api/clay/index.md) - [The old export urls](https://publicwww.com/docs/api/legacy/index.md) ## MCP Server Let an AI assistant search page source for you: Claude, ChatGPT, Cursor, VS Code and more. - [MCP Server](https://publicwww.com/docs/mcp/index.md) - [Signing in](https://publicwww.com/docs/mcp/connecting/index.md) - [Claude](https://publicwww.com/docs/mcp/claude/index.md) - [ChatGPT](https://publicwww.com/docs/mcp/chatgpt/index.md) - [Code editors and CLI agents](https://publicwww.com/docs/mcp/editors/index.md) - [n8n, Make and Zapier](https://publicwww.com/docs/mcp/automation/index.md) - [Tools](https://publicwww.com/docs/mcp/tools/index.md) - [Limits and errors](https://publicwww.com/docs/mcp/limits/index.md) - [For developers](https://publicwww.com/docs/mcp/developers/index.md) ## Use Cases Where PublicWWW has been put to work: research papers, security investigations, marketing, OSINT and videos. - [Use Cases](https://publicwww.com/docs/use-cases/index.md) - [Academic papers](https://publicwww.com/docs/use-cases/papers/index.md) - [Marketing, sales & SEO](https://publicwww.com/docs/use-cases/marketing/index.md) - [OSINT & investigations](https://publicwww.com/docs/use-cases/osint/index.md) - [Security research](https://publicwww.com/docs/use-cases/security/index.md) - [Cryptojacking](https://publicwww.com/docs/use-cases/cryptojacking/index.md) - [Videos & courses](https://publicwww.com/docs/use-cases/videos/index.md) ## Languages The site in thirteen languages, and which characters a search matches. - [Languages](https://publicwww.com/docs/languages/index.md) ## Searching - [Search results](https://publicwww.com/websites/QUERY/): replace QUERY with the url-encoded search string. Quotes around the string mean an exact match. - [Popular values](https://publicwww.com/popular/): the most common JavaScript objects, CSS properties, file names and server headers, counted across the index. - [Top sites](https://publicwww.com/top/): sites ranked inside the index. ## Optional - [Plans and limits](https://publicwww.com/prices.md) - [Use Cases](https://publicwww.com/docs/use-cases/): papers, security research, marketing and OSINT that used PublicWWW - [Terms](https://publicwww.com/terms.html) Automated use goes through the API with a key, not by fetching result pages: the API answers in JSON, XML, CSV, NDJSON or TSV and states its own rate limits. Its OpenAPI description: https://api.publicwww.com/openapi.json An assistant that speaks MCP can search directly: the remote MCP server is `https://api.publicwww.com/mcp` - Streamable HTTP, tools `search`, `account`, `read_docs` (this documentation and the price list in Markdown, also as resources) and seven for clusters (saved lists of sites: create from a search, combine, extract emails, phones, messengers, social profiles and app store links from page source with ready-made presets), sign-in with OAuth or the same key as `Authorization: Bearer`. How to connect: https://publicwww.com/docs/mcp/ Ready-made plugins and client configs: https://github.com/publicwww-com/publicwww-mcp - API clients for Python, JavaScript, PHP, Go and Ruby: https://github.com/publicwww-com