What it is
Perplexity is an AI-powered search engine that combines real-time web search with large language models to deliver direct, cited answers rather than a list of links. Founded in 2022 and headquartered in San Francisco, it has grown into one of the most used AI research tools, processing over 500 million queries in 2025.
The core distinction from other AI assistants is transparency: every response includes clickable citations linking back to the original source, letting users verify claims rather than simply accepting AI-generated output.
Key features
Every Perplexity answer is grounded in live web results, not a static training cutoff. Sources are displayed alongside responses so users can click through and read the original material. This makes it measurably more trustworthy for time-sensitive or fact-sensitive queries than static language models.
The Pro plan gives access to multiple underlying models — including GPT-4o and Claude — letting users switch depending on the task. Deep Research mode runs more extensive multi-source investigations and produces longer, structured reports with full citations.
Follow-up questions work naturally within the same thread, allowing users to progressively narrow down a topic without starting over. The mobile app includes voice input and syncs search history across devices.
Use cases
Perplexity is the tool of choice for research-heavy workflows: fact-checking, competitive intelligence, academic research, staying current on industry developments, and any query where source verification matters.
It works best as a replacement for search-engine-based research rather than as a general-purpose assistant. For creative writing, coding, or long-form content generation, dedicated tools like ChatGPT or Claude remain the stronger options.
