Sonar Reasoning

Name: Sonar Reasoning
Author: Perplexity

PerplexityProprietaryPending Human Review

Sonar Reasoning was Perplexity’s first named reasoning API tier, combining DeepSeek-powered reasoning with real-time web search and cited answers. A provider launch email preserved by its recipient establishes a January 2025 introduction; this record retains month precision because a durable original announcement was not recovered. The service was positioned for questions requiring multi-step analysis rather than the standard Sonar response path. Perplexity’s official changelog confirms that the model was removed from its API on December 15, 2025, with users directed to Sonar Reasoning Pro. Its precise checkpoint architecture, parameters, and training ancestry are not independently established here.

2025-01

Undisclosed DeepSeek-powered reasoning architecture with search augmentation

Proprietary

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Specifications

Architecture: Undisclosed DeepSeek-powered reasoning architecture with search augmentation
License: Proprietary
Type: text
Modalities: text

Benchmark Scores

Advanced Specifications

Model Family: Sonar
API Access: Not Available
Chat Interface: Not Available

Capabilities & Limitations

Capabilities: multi-step reasoningweb searchcitations
Known Limitations: Removed from Perplexity API on December 15, 2025Launch month is supported by a recipient archive of publisher communicationExact internal checkpoint and original model limits are not verified
Notable Use Cases: historical reasoning API evaluationsearch-backed analytical questions
Tool Use Support: Yes

Resources

Related Models

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