Kimi K2 Thinking vs OpenAI o3
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
Moonshot AI · Nov 2025
A trillion-parameter open reasoning agent that can chain 200–300 tool calls — the open-weights agentic standout of late 2025.
OpenAI · Apr 2025
OpenAI's dedicated 2025 reasoning model that pioneered thinking-with-images and agentic tool use within chain-of-thought.
The verdict
Kimi K2 Thinking wins 4 of the 4 benchmarks these models share, against 0 for OpenAI o3. On price the gap is dramatic: Kimi K2 Thinking works out roughly 3.3x cheaper per blended million tokens. Kimi K2 Thinking also takes 262K of context versus 200K for OpenAI o3. And Kimi K2 Thinking is open-weights (Modified MIT), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
Benchmark head-to-head 4–0
Specs & pricing
| Kimi K2 Thinking | OpenAI o3 | |
|---|---|---|
| modhub Index | 67.6 | 68.9 |
| Input price / 1M | $0.6 | $2 |
| Output price / 1M | $2.5 | $8 |
| Context window | 262K | 200K |
| Max output | — | 100K |
| Open weights | yes (Modified MIT) | no |
| Reasoning model | yes | yes |
| Multimodal input | text | text, image |
| Knowledge cutoff | Apr 2025 | May 2024 |
| Released | Nov 2025 | Apr 2025 |
| Example monthly cost* | $9.75 | $32.00 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, Kimi K2 Thinking or OpenAI o3?
- Kimi K2 Thinking wins 4 of the 4 benchmarks these models share, against 0 for OpenAI o3. On price the gap is dramatic: Kimi K2 Thinking works out roughly 3.3x cheaper per blended million tokens. Kimi K2 Thinking also takes 262K of context versus 200K for OpenAI o3. And Kimi K2 Thinking is open-weights (Modified MIT), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
- Which is cheaper, Kimi K2 Thinking or OpenAI o3?
- Kimi K2 Thinking costs $0.6/$2.5 per million input/output tokens, while OpenAI o3 costs $2/$8. For a typical workload of 10M input and 1.5M output tokens per month, that's $9.75 versus $32.00.
- Which model is better for coding, Kimi K2 Thinking or OpenAI o3?
- On SWE-bench Verified — the standard agentic-coding benchmark — Kimi K2 Thinking scores 71.3% versus 69.1% for OpenAI o3, making Kimi K2 Thinking the stronger pick for coding agents.