Best AI Models for Reasoning
The top models for hard reasoning, maths and multi-step problem solving, frontier flagships and dedicated thinking models. All available through one API on thalam.
- 1AIGPT-6 Astra$10.00 / 1M · 1M context · Medium
OpenAI's GPT-6 generation. Frontier reasoning with a 1M-token context, image input, and adjustable reasoning effort.
- 2AIGPT-5.6 Sol$5.00 / 1M · 1M context · Medium
The top tier of OpenAI's GPT-5.6 generation. Frontier reasoning, coding, and agentic work with a 1M-token context and image input.
- 3KMKimi K3$3.00 / 1M · 1M context · Medium
Moonshot's new flagship generation. A 1M-token context and the strongest measured reasoning in our catalog.
- 4DSDeepSeek V4.1 Flash$0.300 / 1M · 1M context · Fast
DeepSeek's V4.1 Flash. A 1M-token context and a 384K output ceiling, with image input, tool calling and reasoning built in.
- 5AIGPT-5.5$5.00 / 1M · 1M context · Medium
OpenAI's flagship GPT-5.5. Top-tier general intelligence, coding, and agentic tasks with a 1M-token context.
- 6GGGemini 3.8 Flash$1.50 / 1M · 1M context · Fast
Google's most capable Flash yet, built on 3.7 for software engineering and autonomous agents. Tops Terminal-bench 2.1 at 89.4% and lifts DeepSWE to 73.7%, with a 1M-token context at the same price as 3.7.
One OpenAI-compatible endpoint for every model above. Pay per token, no subscription, credits never expire.
FAQ
What is the best AI model for reasoning?
Frontier flagships and dedicated "thinking" models (such as the DeepSeek R1 and Kimi thinking lines) lead on hard reasoning and maths. On thalam you can compare them on your own prompts through a single API.
Are reasoning models slower?
Reasoning models often trade latency for accuracy because they generate intermediate steps. A common pattern is to reserve them for hard cases and use a fast model for the rest, a per-request choice on thalam.