> For the complete documentation index, see [llms.txt](https://bugrecon.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://bugrecon.gitbook.io/docs/features-list/scopes-overview/subdomain-scan.md).

# Subdomain scan

The **subdomain scan** discovers subdomains for your target domain(s) using passive, active, and optionally AI-powered enumeration. Adding API keys (Shodan, VirusTotal, Censys, etc.) in the API Keys page improves coverage.

## What it does

* Takes the current domain list for the scan and runs passive and/or active (and optionally AI) subdomain enumeration.
* Updates the scan subdomain list. You can then run port, HTTP, URL, vulnerability, and other scans on these subdomains.

## Options

* **Passive:** Uses third-party sources, public datasets, and databases to find subdomains without direct interaction with the target.
* **Active:** Probes the target domain directly (e.g., DNS brute-forcing, zone transfers) to uncover additional subdomains not found in passive mode.
* **AI:** Leverages AI-assisted techniques (such as generative models and intelligent wordlists) to identify harder-to-find or emerging subdomains.

## Availability

* **Premium** and **Enterprise** only. **Free** and **Basic** users do not have access.
* Uses your scan quota when you run it, and counts against your subdomain target quota (30 targets/period on Premium).

## See also

* [Scans overview](https://github.com/elweth-sec/BugRecon/blob/dev/documentation/gitbook/features/scans-overview.md)


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