GPT-6.1 Sol vs Kimi K3.1 Pro
| Spec | GPT-6.1 Sol | Kimi K3.1 Pro |
|---|---|---|
| Respan Index | 69.8 (#7) | 71.2 (#5) |
| Blended price per 1M | $2 | $3.6 |
| Context window | 1.1M | 1.0M |
| Input / output per 1M | $1 / $5 | $1.8 / $9 |
| Max output | 128K | 1.0M |
| Input | text, vision | text, vision, video |
| Released | 2026-09-29 | 2026-10-23 |
Respan Index by category
Each category is scored 0 to 100, and how far ahead the winner is. Leads under a point are close to even.
| Category | GPT-6.1 Sol | Kimi K3.1 Pro |
|---|---|---|
| Coding | 53.3 GPT-6.1 Sol | 67.7 Kimi K3.1 Pro |
| Agents | 73.1 GPT-6.1 Sol | 69.7 Kimi K3.1 Pro |
| Reasoning | 87.2 GPT-6.1 Sol | 83.7* Kimi K3.1 Pro |
| Knowledge & language | 74.4 GPT-6.1 Sol | 71.5* Kimi K3.1 Pro |
| Human preference | 59.8 GPT-6.1 Sol | 58.5 Kimi K3.1 Pro |
* Estimated: no published scores in that category. How the Respan Index works
Benchmarks both report
GPT-6.1 Sol leads on 2 of the 3 benchmarks both report. Higher is better. Each score links to where it was published.
| Benchmark | GPT-6.1 Sol | Kimi K3.1 Pro |
|---|---|---|
| LMArena Agent (LMArena) | 0.1247 | 0.0596 |
| LMArena WebDev (LMArena) | 1751 | 1695 |
| Terminal-Bench 4.0 (Vals AI) | 55.1% | 63.6% |
FAQ
Is GPT-6.1 Sol better than Kimi K3.1 Pro?
Kimi K3.1 Pro scores 71.2 on the Respan Index (#5), ahead of GPT-6.1 Sol at 69.8 (#7). GPT-6.1 Sol leads on 2 of the 3 benchmarks both report.
Which is cheaper, GPT-6.1 Sol or Kimi K3.1 Pro?
GPT-6.1 Sol lists at $1 input and $5 output per 1M tokens; Kimi K3.1 Pro at $1.8 and $9. GPT-6.1 Sol is 1.8x cheaper per token at list price.
Which has the larger context window?
GPT-6.1 Sol accepts 1.1M tokens and Kimi K3.1 Pro 1.0M tokens.