Findomain – Rust-based utility for discovering subdomains

Findomain is a Rust-based utility for discovering subdomains by querying Certificate Transparency logs and multiple external APIs.

It’s designed for fast enumeration workflows, can resolve discovered hosts for further analysis, and offers ready-to-use Linux binaries alongside source-based installation options.

This is free and open source software.

Key Features

• Subdomain monitoring with support for Discord, Slack, or Telegram webhooks.
• Multi-threaded API querying, helping keep the maximum subdomain search time for any target to around 15 seconds in cases of API timeout.
• Parallel subdomain resolution, capable of resolving about 3,500 subdomains per minute under good network conditions.
• DNS over TLS support.
• Specific IPv4 or IPv6 query support.
• Discovers subdomains without brute force by using Certificate Transparency logs and APIs.
• Can discover only resolved subdomains.
• Can discover subdomain IP addresses for data analysis.
• Reads targets from a user argument (-t) or file (-f).
• Writes all or only resolved subdomains to a single output file specified by the user.
• Writes results to automatically named TXT output file(s).
• Can query the Findomain database created with Subdomains Monitoring for previously discovered subdomains.
• Can import and work with data discovered by other tools.
• Quiet mode for silent operation.
• Cross-platform support.
• Multiple API support.
• Can be used as a subdomain resolver.
• Subdomain wildcard detection for more accurate results.
• Supports subdomain discovery using the brute-force method.
• Supports configuration files in TOML, JSON, HJSON, INI, or YAML format.
• Supports custom DNS IP addresses for fast subdomain resolution, with more than 60 resolutions per second by default, adjustable with the --threads option.

Website: github.com/Findomain/Findomain
Support:
Developer: Findomain
License: GNU General Public License v3.0

Findomain is written in Rust. Learn Rust with our recommended free books and free tutorials.

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