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Subdomain Finder

Discover public subdomains from certificate transparency records. Fast, easy to use and designed with privacy in mind.

Subdomain Finder

Results

Enter a public target to begin.
Simple controlsEverything you need for the task.
Clear resultsReview your output before using it.
No signupGet started without an account.

How it works

1. Add the Required Input

The public URL, domain, IP address, record type, or audit option requested by the checker.

2. Review Subdomain Finder Options

Choose only the settings that apply to the result you need; leave optional controls unchanged when you are unsure.

3. Run Subdomain Finder

Start the task and wait for the interface to return its result or a clear setup message.

4. Verify Before You Use It

Results can vary by location, cache, DNS propagation and temporary server conditions. Confirm important findings with the relevant host or service.

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Frequently Asked Questions

The public URL, domain, IP address, record type, or audit option requested by the checker. Start with a representative input and use only the options needed for your intended result.

A point-in-time observation from the public target and the checks available on this page. Check the result against the original input before using it in a live or important workflow.

Results can vary by location, cache, DNS propagation and temporary server conditions. Confirm important findings with the relevant host or service.

The checker uses the public target you enter to make a diagnostic request. Do not place credentials or private access tokens in a URL.

The page can be used without creating a visitor account. Your browser or device may limit unusually large files or demanding media jobs.

About Subdomain Finder

Subdomain Finder brings the required input, options and result into one focused workflow. Discover public subdomains from certificate transparency records. The result changes when the source data or selected options change, so it is easy to run a second comparison.

Input

What to prepare

The public URL, domain, IP address, record type, or audit option requested by the checker.

Output

What the result represents

A point-in-time observation from the public target and the checks available on this page.

Typical use

A practical example

A practical way to use it is to run a fresh diagnostic after a hosting, DNS, certificate, redirect, content or performance change. Start with a representative input, inspect the first result, then adjust one setting at a time if you need a different outcome.

  • Investigating a public-site problem with Subdomain Finder.
  • Verifying a recent configuration change with Subdomain Finder.
  • Collecting a diagnostic snapshot before troubleshooting with Subdomain Finder.
Verification

Before you use the result

  • Results can vary by location, cache, DNS propagation and temporary server conditions. Confirm important findings with the relevant host or service.
  • Check the result against the original input before using it in a live or important workflow.
Privacy and processing

The checker uses the public target you enter to make a diagnostic request. Do not place credentials or private access tokens in a URL.