Cost Optimized Deep Reasoning For Complex Multi Step Problems

via “reasoning and multi-step problem solving”

Microsoft's 3.8B model with 128K context for edge deployment.

Unique: Achieves 69% MMLU reasoning performance in a 3.8B model through synthetic training data specifically designed for reasoning patterns, significantly outperforming typical SLMs on reasoning benchmarks despite extreme parameter efficiency

vs others: Delivers reasoning capability in 3.8B parameters (vs. Mistral 7B, Llama 3.2 1B which don't emphasize reasoning) while remaining mobile-deployable, trading some accuracy for extreme efficiency and edge compatibility

via “reasoning and multi-step problem decomposition”

TII's 180B model trained on curated RefinedWeb data.

Unique: Achieves strong reasoning performance through scale (180B parameters) and data quality (3.5T meticulously-cleaned RefinedWeb tokens) rather than specialized reasoning fine-tuning, enabling emergent reasoning capabilities across diverse domains without task-specific training.

vs others: Larger parameter count than reasoning-specialized models like Llama 2 70B enables better few-shot reasoning, but lacks explicit chain-of-thought fine-tuning that models like GPT-4 or Claude employ, potentially requiring more sophisticated prompting to achieve comparable reasoning quality.

via “extended-chain-of-thought reasoning with configurable compute allocation”

OpenAI's most powerful reasoning model for complex problems.

Unique: Implements variable-depth reasoning with explicit user-controlled compute budgets rather than fixed token limits, enabling dynamic allocation across problem complexity — users can specify reasoning intensity (low/medium/high) and the model adapts internal chain-of-thought depth accordingly

vs others: Outperforms GPT-4 and Claude on ARC-AGI (87.5% vs ~85%) by allocating more reasoning compute to genuinely hard problems rather than uniform token budgets, and provides explicit cost-quality controls that competitors lack

via “reasoning and step-by-step problem decomposition”

text-generation model by undefined. 95,66,721 downloads.

Unique: Emergent chain-of-thought capability from instruction tuning on reasoning datasets; no explicit reasoning module or symbolic engine — reasoning emerges from learned token prediction patterns that favor intermediate explanation tokens, making it lightweight but probabilistic

vs others: Provides transparent reasoning comparable to GPT-4 on simple problems but with full local control; outperforms Mistral-7B on reasoning tasks due to instruction tuning, but lacks the formal verification and symbolic reasoning of specialized tools like Wolfram Alpha

via “reasoning and complex task decomposition”

Mistral's 12B model with 128K context window.

Unique: Trained explicitly for reasoning tasks with extended 128K context enabling multi-step reasoning chains and complex problem decomposition, though specific reasoning techniques not disclosed

vs others: Larger context window (128K vs 32K in Mistral 7B) enables longer reasoning chains without truncation, improving reasoning quality for complex multi-step problems

via “cost-optimized inference with dynamic reasoning depth”

Latest compact reasoning model with native tool use.

Unique: Implements automatic complexity-based reasoning budget allocation via a pre-inference classifier, reducing costs for simple problems without sacrificing quality on complex ones. This differs from fixed-reasoning-depth models (o1/o3) and non-reasoning models (GPT-4o) which don't adapt reasoning investment.

vs others: More cost-efficient than o1/o3 for mixed workloads (estimated 30-50% cost reduction for typical applications) while maintaining reasoning quality; more capable than GPT-4o on complex problems while being cheaper on simple ones.

via “adaptive-thinking-complexity-aware-reasoning”

Anthropic's most intelligent model, best-in-class for coding and agentic tasks.

Unique: Implements learned complexity routing that estimates problem difficulty from input tokens alone, without requiring explicit user hints or metadata. This is distinct from static reasoning budgets (o1, o1-mini) by dynamically allocating compute per-request based on inferred task characteristics, reducing wasted reasoning on trivial queries.

vs others: More efficient than fixed-reasoning-budget competitors by automatically scaling reasoning effort to task complexity, and more transparent than black-box reasoning models by still exposing thinking tokens when needed for debugging.

via “multi-level reasoning with configurable compute budgets”

Cost-efficient reasoning model with configurable effort levels.

Unique: Implements learned routing at inference time to dynamically allocate reasoning compute across three effort levels without requiring separate model checkpoints, enabling cost-performance tradeoffs within a single model call rather than requiring model selection

vs others: Offers finer cost control than o1 (which has fixed reasoning depth) and lower cost than o3 while maintaining comparable reasoning quality on STEM tasks through adaptive compute allocation

via “chain-of-thought reasoning with reinforcement learning optimization”

text-generation model by undefined. 38,71,385 downloads.

Unique: Uses RL-based training to learn dynamic reasoning token allocation per problem, making reasoning depth adaptive rather than fixed; explicitly optimizes for reasoning quality via reward signals rather than implicit capability from instruction tuning

vs others: Outperforms GPT-4 and Claude on AIME/MATH benchmarks by learning to allocate reasoning compute efficiently, while remaining open-source and deployable locally without API dependencies

via “extended-chain-of-thought reasoning with compute allocation”

OpenAI's reasoning model with chain-of-thought problem solving.

Unique: Native integration of reasoning into the inference architecture with dynamic compute allocation based on problem difficulty, rather than fixed-budget or prompt-instructed reasoning. The model learns to allocate thinking tokens adaptively during training, enabling it to spend more compute on genuinely hard problems.

vs others: Outperforms GPT-4 and other models on reasoning-heavy benchmarks (83.3% on IMO, 89th percentile on Codeforces) because reasoning is baked into the model's weights and inference process, not bolted on via prompting or external tools.

via “deep-reasoning-for-complex-queries”

Exclusively available on the OpenRouter API, Sonar Pro's new Pro Search mode is Perplexity's most advanced agentic search system. It is designed for deeper reasoning and analysis. Pricing is based...

Unique: Allocates extended reasoning resources specifically for complex queries, using iterative search and synthesis rather than single-pass retrieval. The system explicitly reasons about query complexity and adjusts reasoning depth accordingly.

vs others: Deeper reasoning than standard search APIs, and more adaptive than fixed-depth reasoning systems that apply the same analysis to all queries.

via “reasoning and step-by-step problem decomposition”

Meta's latest class of model (Llama 3.1) launched with a variety of sizes & flavors. This 70B instruct-tuned version is optimized for high quality dialogue usecases. It has demonstrated strong...

Unique: Instruction-tuned on datasets containing explicit reasoning traces (e.g., math solutions with working, logic puzzles with step-by-step explanations), enabling the model to learn to generate intermediate reasoning as a learned behavior rather than relying on prompt engineering alone.

vs others: More reliable than base models at producing coherent reasoning chains; comparable to GPT-4 on standard benchmarks but with lower latency and cost, though may underperform on novel reasoning patterns not well-represented in training data.

via “reasoning and chain-of-thought task decomposition”

Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parameters per token....

Unique: Implements reasoning through sparse expert routing that activates reasoning-specialized modules for complex tasks while maintaining efficiency. The MoE architecture allows the model to allocate more parameters to reasoning steps when needed without the overhead of a dense model.

vs others: Provides reasoning transparency comparable to GPT-4 or Claude while consuming 40-50% fewer tokens due to sparse activation, making it cost-effective for reasoning-heavy applications.

via “complex reasoning and chain-of-thought decomposition”

Command R7B (12-2024) is a small, fast update of the Command R+ model, delivered in December 2024. It excels at RAG, tool use, agents, and similar tasks requiring complex reasoning...

Unique: Command R7B's reasoning is optimized for RAG and tool-use contexts, where intermediate steps can reference retrieved documents or tool outputs, enabling grounded reasoning that combines external knowledge with logical inference

vs others: Outperforms GPT-4 on MATH and AIME benchmarks when combined with tool use for calculation, because it can delegate computation to tools rather than attempting symbolic math in-context

via “extended reasoning with implicit chain-of-thought”

Grok 4 is xAI's latest reasoning model with a 256k context window. It supports parallel tool calling, structured outputs, and both image and text inputs. Note that reasoning is not...

Unique: Implicit reasoning allocation based on problem complexity, with reasoning traces integrated into output without explicit token budget management, contrasting with OpenAI's explicit reasoning token approach

vs others: More transparent reasoning than GPT-4o (which hides reasoning) but less controllable than o1 (which offers explicit reasoning token budgets); better for exploratory reasoning where depth is problem-dependent

via “logical reasoning and problem-solving with step-by-step decomposition”

Meta's latest class of model (Llama 3) launched with a variety of sizes & flavors. This 70B instruct-tuned version was optimized for high quality dialogue usecases. It has demonstrated strong...

Unique: Instruction-tuning explicitly optimizes for chain-of-thought reasoning patterns, enabling the model to articulate intermediate steps and self-correct. 70B scale provides sufficient capacity for multi-step reasoning without losing coherence.

vs others: Better reasoning transparency than smaller models and comparable to GPT-4 on many reasoning tasks at lower cost, though specialized reasoning models or symbolic solvers may outperform on highly constrained domains like formal mathematics.

via “mathematical-problem-solving-with-step-by-step-reasoning”

DeepSeek-V3.1 is a large hybrid reasoning model (671B parameters, 37B active) that supports both thinking and non-thinking modes via prompt templates. It extends the DeepSeek-V3 base with a two-phase long-context...

Unique: Implements explicit reasoning phase specifically optimized for mathematical decomposition, allowing the model to verify intermediate steps before producing final answers, rather than generating answers directly.

vs others: More reliable for complex math than GPT-4 due to explicit verification phase, and more transparent than o1 (which hides reasoning) by allowing users to request step-by-step explanations.

via “reasoning-focused problem decomposition and chain-of-thought”

This is Mistral AI's flagship model, Mistral Large 2 (version mistral-large-2407). It's a proprietary weights-available model and excels at reasoning, code, JSON, chat, and more. Read the launch announcement [here](https://mistral.ai/news/mistral-large-2407/)....

Unique: Trained specifically on chain-of-thought datasets to prioritize reasoning steps, using attention mechanisms that weight intermediate reasoning tokens higher than direct answers, enabling more transparent problem-solving

vs others: Comparable to GPT-4's reasoning on complex problems, while maintaining lower latency and cost; outperforms Llama 2 on multi-step reasoning due to larger parameter count and specialized training

via “multi-step problem solving with extended context windows”

DeepSeek R1 is here: Performance on par with [OpenAI o1](/openai/o1), but open-sourced and with fully open reasoning tokens. It's 671B parameters in size, with 37B active in an inference pass....

Unique: Achieves o1-level reasoning performance on multi-step problems through a 671B parameter model with mixture-of-experts efficiency, exposing full reasoning traces for validation. Unlike o1, the reasoning process is transparent and the model weights are open-source, enabling custom fine-tuning for domain-specific problem types.

vs others: Comparable to o1 on reasoning benchmarks but with transparent reasoning tokens and lower API costs, versus GPT-4 which lacks explicit reasoning and requires more prompt engineering for complex multi-step problems.

via “reasoning and multi-step problem decomposition”

Qwen3-235B-A22B-Instruct-2507 is a multilingual, instruction-tuned mixture-of-experts language model based on the Qwen3-235B architecture, with 22B active parameters per forward pass. It is optimized for general-purpose text generation, including instruction following,...

Unique: Instruction-tuned on chain-of-thought examples enabling the model to naturally decompose reasoning without requiring explicit prompting frameworks or external planning systems, with MoE architecture potentially routing complex reasoning to specialized parameter subsets

vs others: More natural reasoning flow than base models due to instruction-tuning, though may underperform specialized reasoning models (o1, DeepSeek-R1) on very complex mathematical or logical problems requiring extensive search