Apisearch
Algolia
Apache Solr
ElasticSearch
Google Custom Search Engine
Site Search 360
Sphinx (search engine)
Swiftype
Search engine composer
Zoom Search Engine
A1 Website Search Engine
Site Search 360
Google Custom Search Engine
Findberry
Zoom Website Search Engine
MailChimp
Apisearch Search engine composerAlgolia - Algolia's Search API makes it easy to deliver a great search experience in your apps & websites. Algolia Search provides hosted full-text, numerical, faceted and geolocalized search.
Zoom Search Engine - Add search to your website, Optical Character Recognition* (OCR) for images and PDF, Huge indexing optimizations Multi-threaded Offline Indexing
Apache Solr - Solr is an open source enterprise search server based on Lucene search library, with XML/HTTP and...
A1 Website Search Engine - Create search engines for online and offline website content.
ElasticSearch - Elasticsearch is an open source, distributed, RESTful search engine.
Site Search 360 - Site Search 360 enhances and improves your built-in CMS or product search with autocompletion, semantic search, filters, facets, detailed analytics, and a whole lot of customization options.