OpenAI
GPT-5.6 Sol
Frontier GPT-5.6 model for complex professional work, coding, and agentic workflows
- Context
- 1.1M
- Max output
- 128K
- Input / 1M
- $5.00
- Output / 1M
- $30.00
- Output speed
- —
Accepts
- Text input
- Image input
- PDF input
Produces
- Text output
AI model comparison
Compare recorded price, context, output limits, speed, latency, capabilities, and input/output support. Every missing value stays visible, and unsourced benchmarks are excluded.
GPT-5.6 Sol and Grok 4.5 both come up when teams are choosing a model for production work, and the honest answer usually depends on your workload rather than a leaderboard. This page puts their published specifications side by side — context window, token pricing, supported inputs and outputs — so you can see where they actually differ.
OpenAI
Frontier GPT-5.6 model for complex professional work, coding, and agentic workflows
Accepts
Produces
xAI
xAI's latest Grok for chat, coding, agentic tools, and lower hallucination risk
Accepts
Produces
At a glance
This is a directional summary of the values recorded in this directory—not a universal quality verdict. Test the finalists on your own prompts before committing.
Where GPT-5.6 Sol leads in recorded data
Where Grok 4.5 leads in recorded data
Context capacity
Higher listed limit
GPT-5.6 Sol:1.1M
Grok 4.5:500K
GPT-5.6 Sol
Maximum output
Higher listed limit
GPT-5.6 Sol:128K
Grok 4.5:500K
Grok 4.5
Input price
Lower recorded price
GPT-5.6 Sol:$5.00
Grok 4.5:$2.00
Grok 4.5
Output price
Lower recorded price
GPT-5.6 Sol:$30.00
Grok 4.5:$6.00
Grok 4.5
Output speed
Higher recorded throughput
GPT-5.6 Sol:—
Grok 4.5:—
No complete comparison
Time to first token
Lower recorded latency
GPT-5.6 Sol:—
Grok 4.5:—
No complete comparison
Intelligence Index
Higher directory index
GPT-5.6 Sol:—
Grok 4.5:—
No complete comparison
Evidence
A score appears only when both records include a verified source. It is not treated as a universal ranking.
Specifications
| Specification | GPT-5.6 Sol | Grok 4.5 |
|---|---|---|
| Provider | OpenAI | xAI |
| Model family | gpt-sol | grok |
| Accepted inputs | text, image, pdf | text, image |
| Produced outputs | text | text |
| Context window | 1.1MRecorded lead | 500K |
| Max output | 128K | 500KRecorded lead |
| Intelligence Index | — | — |
| Input price / 1M | $5.00 | $2.00Recorded lead |
| Output price / 1M | $30.00 | $6.00Recorded lead |
| Output speed | — | — |
| Time to first token | — | — |
| Reasoning mode | Documented | Documented |
| Tool calling | Documented | Documented |
| Image input | Documented | Documented |
| Audio input | Not documented | Not documented |
| Structured output | Documented | Documented |
| License | Proprietary | Proprietary |
| Released | Jul 9, 2026 | Jul 8, 2026 |
Workload guidance
On the published numbers, GPT-5.6 Sol accepts the larger context window and Grok 4.5 is cheaper per input token. Which matters more depends on whether your bottleneck is document size or spend — the table above has the exact figures.
Provenance
Prices and hosted performance can change. SyncDev records source references and clearly separates documented specifications from measured values; confirm commercial terms with the provider before deployment.
GPT-5.6 Sol
OpenAI · model record and recorded source
Grok 4.5
xAI · model record and recorded source
Choose any two approved model records and review them with the same evidence rules.