Loading benchmark catalogue
Compare performance benchmarks, coding intelligence, reasoning evaluations, context limits, and API economics between Step 5 Preview (StepFun) and GPT-6.1 Sol (OpenAI).
| Metric / Capability | Step 5 Preview | GPT-6.1 Sol |
|---|---|---|
| Developer / Organization | StepFun | OpenAI |
| Release Date | 2026-10-08 | 2026-09-29 |
| Deployment / Weights | Open Weights | Proprietary Cloud API |
| Context Window | 1.0M tokens (1,048,576 tokens) | 1.1M tokens (1,050,000 tokens) |
| Input Pricing (/1M Tokens) | Free (Open Weights) | $2 |
| Output Pricing (/1M Tokens) | Free (Open Weights) | $10 |
| Benchmark / Domain | Step 5 Preview | GPT-6.1 Sol | Advantage |
|---|---|---|---|
Artificial Analysis Intelligence Index Composite index aggregating 10+ evaluations of general reasoning and knowledge. | 43.7% | 51.8% | GPT-6.1 Sol (+19%) |
Artificial Analysis Coding Agent Index v2.0 Composite index of coding-agent systems (model + harness) across FrontierCode v1.1, SWE-Atlas-QnA, and Terminal-Bench v4. | 43.1% | 54.1% | GPT-6.1 Sol (+26%) |
Terminal-Bench 4.0 Sandboxed command-line tasks requiring shell and file-system operation. | 33.3% | 58.2% | GPT-6.1 Sol (+75%) |
ARC-AGI-2 Novel visual grid puzzles requiring abstract rule induction. | — | 94.2% | — |
GPQA Diamond Graduate-level physics, chemistry, and biology questions written by domain experts. | 93.5% | — | — |
Humanity's Last Exam Expert-written questions across hundreds of disciplines designed to resist saturation. | 46.5% | — | — |
FrontierMath v2 (Tiers 1-3) Unpublished, research-level mathematics problems across Tiers 1-3. | — | 93.7% | — |
Design Arena ELO Human-preference ELO across UI, 3D, data-visualization, and game-dev generations. | — | 1437 | — |
GPT-6.1 Sol outperforms Step 5 Preview across 3 evaluated benchmarks compared to 0 for Step 5 Preview, excelling in Artificial Analysis Intelligence Index, Artificial Analysis Coding Agent Index v2.0, Terminal-Bench 4.0.
GPT-6.1 Sol has the larger context capacity of 1.1M tokens (1,050,000 tokens), compared to 1.0M tokens for Step 5 Preview.
Step 5 Preview is more cost-effective. Input tokens cost $Free (Open Weights)/M tokens vs $2/M tokens for GPT-6.1 Sol.
Step 5 Preview is an open-weights model. GPT-6.1 Sol is a proprietary cloud API.
Analyze 130+ models side-by-side using interactive radar charts, cost-efficiency quadrant plots, and live dataset filters on the full NeuBench index.
Open Interactive Comparator