Subfinder

Domain OSINTDNS Investigation

Automated checks passed
Checked 8/26/2026

Subfinder is an open-source passive subdomain discovery tool. Coverage depends on enabled sources, API access, rate limits, and upstream data, so results should not be treated as a complete inventory.

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Features

✓40+ passive sources
✓Fast concurrent scanning
✓API key support
✓Output filtering
✓JSON/CSV export
✓Silent mode

Limitations

✗Passive only (no brute force)
✗Some sources need API keys for best results

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Tool Details

Interface CLI

Pricing Free

Skill Level Intermediate

Open Source Yes ✓

Maintenance Reported active

Reported Update 2024-12

Platforms

🪟 windows🐧 linux🍎 macos🐉 kali

Subfinder

Features

Limitations

Related Tools

SecurityTrails

Censys

domain-digger

Tool Details

Platforms

Accepts Input Types

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