Los motores de búsqueda que actualmente utiliza theHarvester son (información extraída de su propia página de proyecto en Github):

• baidu: Baidu search engine - **http://www.baidu.com/**
• bing: Microsoft search engine - **https://www.bing.com/**
• bingapi: Microsoft search engine, through the API (Requires an API key, see below.)
• bufferoverun: Uses data from Rapid7's Project Sonar.
• ***https://www.rapid7.com/research/project-sonar/***
• certspotter: Cert Spotter monitors Certificate Transparency logs.
• ***https://sslmate.com/certspotter/***
• crtsh: Comodo Certificate search - **https://crt.sh/**
• dnsdumpster: DNSdumpster search engine - **https://dnsdumpster.com/**
• dogpile: Dogpile search engine - **https://www.dogpile.com/**
• duckduckgo: DuckDuckGo search engine - **https://duckduckgo.com/**
• exalead: a Meta search engine - **http://www.exalead.com/search/**
• github-code: GitHub code search engine (Requires a GitHub Personal Access Token, see below.) - **https://github.com/**
• google: Google search engine (Optional Google dorking.).
• ***https://www.google.com/***
• hackertarget: Online vulnerability scanners and network intelligence to help organizations - **https://hackertarget.com/**
• hunter: Hunter search engine (Requires an API key, see below.) –
• ***https://hunter.io/***
• intelx: Intelx search engine (Requires an API key, see below.).