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Free AI-powered academic search engine indexing 236M+ papers, for researchers wanting semantic literature discovery and an augmented reader.
Well-adopted AI research assistant for finding papers, summarizing, and extracting data at scale.
AI language coach offering conversational practice with real-time feedback across 130+ languages.
Interactive learning app with an AI tutor for math, coding, science and data-visual, adaptive lessons for all ages.
AI platform that scores speaking, writing, reading and listening in 80+ languages for pre-hire language screening.
No public pricing
No public pricing
Free trial available
No public pricing
No public pricing
- ✦AI-powered semantic search across 236M+ papers
- ✦Semantic Reader for augmented, contextual paper reading
- ✦Free public API for paper search and metadata
- ✦Author and topic discovery
- ✦Citation graph exploration
- ✦Beta program for new features
- ✦AI-enabled systematic reviews
- ✦Research reports
- ✦Upload your own PDFs
- ✦Quick summaries
- ✦Source quotes
- ✦Question answering
- ✦Conversational practice with AI tutors
- ✦Real-time personalized feedback and corrections
- ✦Dialogue, sentence, word, call, photo, and debate modes
- ✦Voice interaction with natural AI voices
- ✦Grammar courses and language certificates
- ✦130+ languages on web, iOS, and Android
- ✦Personal AI tutor (Koji)
- ✦Visual, interactive lessons
- ✦Adaptive practice based on mastery
- ✦Courses in math, CS, science and data
- ✦Gamified streaks, levels and daily goals
- ✦iOS and Android apps
- ✦Scenario-based, open-response speaking and writing tests
- ✦CEFR score reports with skill-level feedback
- ✦Pronunciation and accent evaluation
- ✦Coverage of 80+ languages
- ✦Proctoring and cheating-prevention controls
- ✦Admin dashboard with shareable results
- ✦White labeling and multi-factor authentication
- →Researchers searching scientific literature across disciplines
- →Developers building applications on top of scholarly data via the API
- →Students exploring citation networks for a topic
- →Librarians and academics needing free literature discovery tools
- →Speeding up literature reviews
- →Automating systematic reviews and meta-analyses
- →Learning about new domains
- →Data extraction in rigorous systematic literature reviews
- →Self-learners practicing conversational fluency
- →Business teams training employees in new languages
- →Students supplementing classroom language education
- →Learning math and coding by doing
- →Getting adaptive tutoring outside class
- →Building STEM intuition
- →Daily skill practice
- →Pre-employment language screening
- →BPO and customer-service hiring
- →HR and placement testing
- →Learning-and-development assessment
- →Enterprise global hiring