Perplexity Sonar is Perplexity AI's API offering that enables developers to integrate Perplexity's real-time web search and AI reasoning capabilities into their own applications. It provides online LLM models that answer questions with up-to-date information retrieved from the web and synthesized with AI reasoning — making it straightforward to build search-grounded AI applications without managing search infrastructure. Developers building research tools, news aggregators, fact-checking systems, and knowledge applications use Perplexity Sonar to power AI responses that are both intelligent and reliably current.