---
title: "Subdomain Lookup - List subdomains for a domain | Web ToolBox"
description: "List subdomains for a domain with sorting and filtering. You can copy the list or export it as CSV. Useful for reviewing your own domain footprint or preparing a security review."
canonical_url: "https://web-toolbox.dev/en/tools/subdomain-lookup"
meta:
  author: K
  "og:description": "List subdomains for a domain with sorting and filtering. You can copy the list or export it as CSV. Useful for reviewing your own domain footprint or preparing a security review."
  "og:image": "https://web-toolbox.dev/og/en/tools/subdomain-lookup-2551d07a.png"
  "og:image:alt": "Subdomain Lookup"
  "og:image:height": "630"
  "og:image:width": "1200"
  "og:title": "Subdomain Lookup - List subdomains for a domain | Web ToolBox"
---

> Index of every page on this site: [llms.txt](https://web-toolbox.dev/llms.txt)

# **Subdomain Lookup**

List subdomains associated with a domain

## What is Subdomain Lookup?

Subdomain Lookup lists subdomains related to a domain. Enter a domain and the tool shows subdomains found in a public database, together with the date each one was last observed.

It is useful for reviewing your own domain footprint, doing DNS-related research, or getting a quick look at the publicly visible structure of another domain.

## How to Use

1. Enter the domain you want to check and run the search. If you paste a URL, only the domain part is used.
2. Filter and sort the loaded subdomains.
3. Copy the shown rows in one go or export them as CSV. Use "Load More" to fetch more results.

## Reading the Results

### Subdomain

Each discovered subdomain is listed, and you can open its URL from the name. The root domain itself is also included in the results.

### Last Seen

The date when the subdomain was last observed. Sorting by newest first puts recently observed subdomains at the top.

## Use Cases

- Reviewing subdomains under your own domain
- Understanding publicly visible subdomains before a security check
- Getting a quick picture of another domain's public service structure

## Things to Keep in Mind

- The lookup relies on public information, so subdomains that were never exposed publicly will not appear. Results are not exhaustive either
- A last-seen date is an observation point, not a guarantee that the subdomain is still active
- Filtering, copying, and CSV export cover the rows you have loaded
- If you search the same domain again within a short period, the cached result from the previous search may be returned for a while

```json
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```

## Sitemap

See the full [sitemap](https://web-toolbox.dev/sitemap.md) for all pages.