AI model comparison
Inkling vs GPT-5.1
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
Thinking Machines
Inkling
Inkling is an open-weight multimodal mixture-of-experts model from Thinking Machines Lab, with 41B active parameters out of 975B total.
- Input / 1M
- $1
- Output / 1M
- $4.05
- Context
- 524K
OpenAI
GPT-5.1
GPT-5.1 is the latest frontier-grade model in the GPT-5 series, offering stronger general-purpose reasoning, improved instruction adherence, and a more natural conversational style compared to GPT-5.
- Input / 1M
- $1.25
- Output / 1M
- $10
- Context
- 400K
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
Inkling
1.9x cheaper for a typical chat
Higher intelligence score
Inkling
25 vs 24.7 on Artificial Analysis
Larger context window
Inkling
524K vs 400K tokens
Newer release
Inkling
Released July 17, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
GPT-5.124.7Coding index
GPT-5.149.4Agentic index
GPT-5.1Not availablePricing
Inkling vs GPT-5.1 API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | GPT-5.1 | |
|---|---|---|
| Input tokensPer 1M tokens | $1 | $1.25 |
| Output tokensPer 1M tokens | $4.05 | $10 |
| Cached input (read)Per 1M tokens | $0.17 | $0.13 |
| Cache writePer 1M tokens | Not available | Not available |
| 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-5.1$7.50Coding task
30K in, 4K out
GPT-5.1$77.50$43.75 cachedLong document summary
150K in, 2K out
GPT-5.1$207.50$38.75 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | GPT-5.1 | |
|---|---|---|
| Context window | 524K tokens | 400K tokens |
| Max output | 472K tokens | 128K tokens |
| Input types | Audio, Image, Text | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | Max, High, Medium, Low, Minimal, None | High, Medium, Low, None |
| Default reasoning effort | High | None |
| Release date | July 17, 2026 | November 13, 2025 |
Features
Supported features
API features available for each model.
| Metric | GPT-5.1 | |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Not supported | Supported |
| JSON mode | Not supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Supported | Not supported |
| Stop sequences | Supported | Not supported |
| Deterministic seed | 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.
Our take
Inkling is 1.9x cheaper for a typical chat. Inkling scores higher on the Artificial Analysis Intelligence Index (25 vs 24.7). Inkling has the larger context window (524K vs 400K 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 Inkling or GPT-5.1 cheaper?
Inkling is cheaper for a typical chat (2K input tokens and 500 output tokens). Inkling costs $1 per 1M input tokens and $4.05 per 1M output tokens, while GPT-5.1 costs $1.25 per 1M input tokens and $10 per 1M output tokens.
Which has a bigger context window, Inkling or GPT-5.1?
Inkling supports up to 524K tokens of context, compared with 400K for GPT-5.1.
Is Inkling smarter than GPT-5.1?
On the Artificial Analysis Intelligence Index, Inkling scores 25 and GPT-5.1 scores 24.7, putting Inkling ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.
Can I use Inkling and GPT-5.1 at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Inkling and GPT-5.1 answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to Inkling and GPT-5.1 at the same time. Compare the answers side by side and keep the best one.