AI model comparison
Step 5 Preview vs GPT-6.1 Sol
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
StepFun
Step 5 Preview
Step 5 Preview is StepFun's flagship model for agentic work, built on a sparse Mixture-of-Experts architecture (27B active / 600B total parameters).
- Input / 1M
- $1
- Output / 1M
- $2.70
- Context
- 1M
OpenAI
GPT-6.1 Sol
GPT-6.1 Sol is an upgrade to GPT-6 Sol from OpenAI, positioned below the flagship GPT-6 Astra in the GPT-6 series.
- Input / 1M
- $2
- Output / 1M
- $10
- Context
- 1.05M
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
Step 5 Preview
2.7x cheaper for a typical chat
Higher intelligence score
Tie
Not enough benchmark data
Larger context window
GPT-6.1 Sol
1.05M vs 1M tokens
Newer release
Step 5 Preview
Released October 8, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
GPT-6.1 Sol51.8Coding index
GPT-6.1 SolNot availableAgentic index
GPT-6.1 SolNot availablePricing
Step 5 Preview vs GPT-6.1 Sol API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | GPT-6.1 Sol | |
|---|---|---|
| Input tokensPer 1M tokens | $1 | $2 |
| Output tokensPer 1M tokens | $2.70 | $10 |
| Cached input (read)Per 1M tokens | $0.05 | $0.10 |
| Cache writePer 1M tokens | Not available | $2.50 |
| Long-context pricingPer 1M tokens, for very long prompts | Same rate at any length | $4 in / $15 out above 272K |
| Web searchPer request | Not available | $0.01 |
What it costs in practice
Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.
Chat message
2K in, 500 out
GPT-6.1 Sol$9Coding task
30K in, 4K out
GPT-6.1 Sol$100$43 cachedLong document summary
150K in, 2K out
GPT-6.1 Sol$320$35 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | GPT-6.1 Sol | |
|---|---|---|
| Context window | 1M tokens | 1.05M tokens |
| Max output | 64K tokens | 128K tokens |
| Input types | Image, Text, Video | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | High, Medium, Low | Max, Extra high, High, Medium, Low |
| Default reasoning effort | Medium | Medium |
| Release date | October 8, 2026 | September 29, 2026 |
Features
Supported features
API features available for each model.
| Metric | GPT-6.1 Sol | |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Supported | Not supported |
| Stop sequences | Supported | Not supported |
| Deterministic seed | Not supported | Supported |
| Verbosity control | Not supported | Supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
- Step 5 Preview vs DeepSeek V4.1 Flash
- Step 5 Preview vs GLM 5.3 Flash
- Step 5 Preview vs MiMo-V2.6-Flash
- Step 5 Preview vs Hy4 preview
- Step 5 Preview vs GPT-6 Luna
- Step 5 Preview vs DeepSeek V4 Flash 0731
- Step 5 Preview vs Claude Opus 5.5
- Step 5 Preview vs GLM 5.3
- Step 5 Preview vs DeepSeek V4 Flash 0423
- Step 5 Preview vs Hy3
- Step 5 Preview vs Claude Sonnet 5.5
- Step 5 Preview vs Gemini 3.8 Flash
- Step 5 Preview vs DeepSeek V4 Pro 0813
- Step 5 Preview vs Gemini 3 Flash Preview
- Step 5 Preview vs Claude Opus 5
- Step 5 Preview vs GPT-6 Astra
- Step 5 Preview vs Qwen3.8 27B
- Step 5 Preview vs Gemini 2.5 Flash
- Step 5 Preview vs Claude Fable 5.1
- Step 5 Preview vs GLM 5.3 FlashX
- Step 5 Preview vs GPT-5.6 Luna Pro
GPT-6.1 SolView full model details- GPT-6.1 Sol vs Claude Opus 5.5
- GPT-6.1 Sol vs Claude Sonnet 5.5
- GPT-6.1 Sol vs Claude Fable 5.1
- GPT-6.1 Sol vs GPT-6 Astra
- GPT-6.1 Sol vs Claude Opus 5
- GPT-6.1 Sol vs Claude Fable 5
- GPT-6.1 Sol vs Muse Spark 1.3
- GPT-6.1 Sol vs GPT-6 Sol
- GPT-6.1 Sol vs GPT-5.6 Sol
- GPT-6.1 Sol vs Grok 4.7
- GPT-6.1 Sol vs DeepSeek V4.1 Flash
- GPT-6.1 Sol vs GLM 5.3 Flash
- GPT-6.1 Sol vs GLM 5.3
- GPT-6.1 Sol vs MiMo-V2.6-Flash
- GPT-6.1 Sol vs Hy4 preview
- GPT-6.1 Sol vs Kimi K3
- GPT-6.1 Sol vs GPT-6 Luna
Our take
Step 5 Preview is 2.7x cheaper for a typical chat. GPT-6.1 Sol has the larger context window (1.05M vs 1M tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.
FAQ
Frequently asked questions
Is Step 5 Preview or GPT-6.1 Sol cheaper?
Step 5 Preview is cheaper for a typical chat (2K input tokens and 500 output tokens). Step 5 Preview costs $1 per 1M input tokens and $2.70 per 1M output tokens, while GPT-6.1 Sol costs $2 per 1M input tokens and $10 per 1M output tokens.
Which has a bigger context window, Step 5 Preview or GPT-6.1 Sol?
GPT-6.1 Sol supports up to 1.05M tokens of context, compared with 1M for Step 5 Preview.
Can I use Step 5 Preview and GPT-6.1 Sol at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Step 5 Preview and GPT-6.1 Sol answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to Step 5 Preview and GPT-6.1 Sol at the same time. Compare the answers side by side and keep the best one.