Perplexity

Perplexity is the leading AI-powered search engine, combining real-time web search with AI synthesis and proper citations. Unlike ChatGPT's browsing, Perplexity is purpose-built for research and presents every answer with inline numbered sources. Pro Search runs multi-step research; Deep Research autonomously investigates and produces structured reports. Pro tier ($20/month) unlocks model choice across Claude, GPT and Perplexity's own Sonar models, 300+ Pro Searches/day, file uploads, and Spaces (persistent research workspaces). Best for: research, fact-checking, current events, competitive analysis, and any workflow where source verification matters.