Search engines, including web search engines, selection-based search engines, metasearch engines, desktop search tools, and web portals and vertical market websites have a search facility for online databases.

By content/topic

General

† Main website is a portal

Geographically localized

Accountancy

Business

Computers

Content

Dark web

Education

General: Academic materials only:

Enterprise

Events

Food and recipes

Genealogy

Job

Legal

Medical

Mobile/handheld

News

People

Real estate/property

Television

Travel

Video

Video games

By data type

Search engines dedicated to a specific kind of information

Maps

Multimedia

Price

Source code

BitTorrent

These search engines work across the BitTorrent protocol.

Blog

By model

Search appliances

Desktop search engines

Desktop search engines listed on a light purple background are no longer in active development.

Child-safe search engines

Metasearch engines

Natural language

Open-source search engines

Web search engine

Enterprise search

P2P search engines

Privacy search engines

Social and environmental focus

Semantic browsing engines

Social search engines

Usenet

Visual search engines

By popularity

Defunct or acquired search engines