How to use httpx: probe lists of hosts for live web servers

Install httpx with Go

httpx requires Go 1.26.10 or newer to install successfully. If you have Go set up, the README gives a single install command that fetches the tool from its repository.

The project's install documentation, linked from the README, has more detail on installing httpx.

• Check that your Go version meets the minimum before installing.
• Run the install command from a terminal.

Check the help and available flags

Run httpx with the help flag to list every switch the tool supports. The flags are grouped into sections: INPUT, PROBES, HEADLESS, MATCHERS, EXTRACTOR and FILTERS.

Use the help output as your reference, since the flags are many and some are only needed for specific jobs.

Probe a single target or a list of hosts

Use -u to probe one host or URL. To work through many targets, put one host per line in a file and pass it with -l. httpx accepts hosts, URLs and CIDR ranges as input.

Add probe flags such as -sc for status code, -title for page title, -server for the web server name, and -td for technology detection. Probes that are on by default include URL, title, status code and web server, so you only need flags for extra data.

• -u: probe a single target host or URL.
• -l: read targets from an input file, one per line.
• -sc: show the response status code.
• -title: show the page title.
• -server: show the server name.
• -td: detect technologies based on the Wappalyzer dataset.

Filter results to the servers you care about

Matchers keep only responses that fit a rule, while filters remove responses that fit one. This is the main way to cut a long list of subdomains down to live web servers that match your criteria.

Matchers include -mc for status codes and -ms for a string in the response. Filters include -fc to drop status codes. The help output lists the full set, including regex matchers and filter options for duplicates.

• -mc 200,302: keep only responses with these status codes.
• -ms admin: keep responses containing the string admin.
• -fc 403,401: drop responses with these status codes.
• -fd: filter out near-duplicate responses, keeping only the first.

Use the output in other tools

httpx prints results you can read directly or pass on to other tools. The README notes that httpx supports JSON and CSV output, and it can be combined with pipes in a shell script. Keep your scripts simple and check results before acting on them.

Because httpx is a command-line tool, it fits into a script that runs on a schedule or chains with other commands. It has no graphical interface.

• Use the help output to find the exact output options your version supports.
• Pipe the list of results into another command for further processing.

Use httpx responsibly

Only probe systems you are authorized to test. httpx can generate heavy traffic when run against large lists, and the README notes it is widely used for pentesting, so unauthorized scanning can cause real harm.

The README also warns that running httpx as a service may pose security risks. The project was built mainly as a standalone CLI tool, so use it as one and add your own security measures if you do anything else.