Sonar Reasoning Pro

Sonar Reasoning Pro is Perplexity's reasoning-focused entry in the Sonar family of search-augmented language models, sitting alongside Sonar Pro and the later Sonar Deep Research variant. According to OpenRouter's March 2025 announcement, the model is described as offering advanced reasoning capabilities powered by DeepSeek R1 with Chain of Thought (CoT), making it well suited for sophisticated queries that require detailed analysis and extensive sourcing rather than simple lookups. The combination of a DeepSeek R1 reasoning backbone with Perplexity's search infrastructure positions it as a hybrid system that blends live retrieval with explicit step-by-step inference, distinguishing it from the lighter Sonar base model.

In practical terms, Sonar Reasoning Pro is aimed at users who need structured, multi-step reasoning grounded in fresh web evidence, such as analytical research, detailed comparative breakdowns, and questions that benefit from transparent reasoning traces. Perplexity's March 2025 Sonar improvements introduced three search depth modes (High, Medium, and Low) across the lineup, letting callers trade off thoroughness against cost, and the company specifically noted simplified billing for Sonar Pro and Sonar Reasoning Pro users, including waiving charges for citations tokens. This makes the model a good fit when answer provenance and reasoning depth matter more than raw speed, while the tiered modes give room to scale usage down for simpler questions.