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Model comparison
GPT-6 Astra vs GPT-5.6 Sol
Compare GPT-6 Astra and GPT-5.6 Sol using the same provider-sourced text & reasoning rubric. No mystery score and no invented benchmark ranking.
Facts checked September 4, 2026
Estimate your cost
Set your usage. Your estimate updates as you type.
Example: 6,000 input tokens for 10 pages, plus a 500-token summary. Page lengths vary; adjust the numbers below.
One run sends your input to the model once and receives an answer. Tokens are pieces of text: input is what you send, output is the answer you receive.
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How this estimate works
Estimates exclude taxes, tools, cache storage/writes, free allowances and custom discounts. Image estimates cover output only, not prompt or reference-image charges. Quality modes differ by model. Unlisted settings are not treated as free.
| Model | Access | Estimated total (USD) |
|---|---|---|
| GPT-5.6 SolOpenAI | OpenAI | $0.034 |
| GPT-6 AstraOpenAI | OpenAI | $0.085 |
Quick take
GPT-6 Astra
OpenAI's most capable model for difficult end-to-end work, combining frontier reasoning with a million-token context window and a broad set of agent tools.
Best for
- Complex, long-running agent workflows
- Repository-scale coding and computer use
- Research and document creation with several tools
Watch out for
Access is still rolling out, fine-tuning is not supported, and requests above 272K input tokens use higher rates across the full request. Confirm access and measure total task cost before standardizing on Astra.
GPT-5.6 Sol
OpenAI's flagship general model for difficult coding, analysis, and professional work, with a very large context window and a broad native tool set.
Best for
- Complex coding and repository work
- Long-document analysis with tools
- General agents that need OpenAI's hosted tool ecosystem
Watch out for
Budget with the long-context multiplier, cached-input rules, tool charges, and reasoning tokens—not only the headline input/output rate.
Compare the published facts
GPT-6 Astra vs GPT-5.6 Sol
Values use each provider's own published units and limits. A blank means the provider did not publish a directly comparable value in the sources reviewed.
| Text & reasoning | GPT-6 Astra | GPT-5.6 Sol |
|---|---|---|
| Context windowMaximum combined prompt and working context documented by the provider. | 1.05M tokens | 1.05M tokens |
| Maximum outputProvider-published response limit, where available. | 128K tokens | 128K tokens |
| Knowledge cutoffLatest reliable knowledge date explicitly published by the model provider. Search and connected tools can retrieve newer information but do not change the model's built-in cutoff. | April 30, 2026 | February 16, 2026 |
| Input priceCurrent standard list price per million input tokens unless noted. | $10 / 1M | $4 / 1M |
| Output priceCurrent standard list price per million output tokens unless noted. | $50 / 1M | $20 / 1M |
| InputsMedia types accepted by the listed model endpoint. | Text, image | Text, image |
| Tools & agentsSelected native tools and agent-building capabilities, not an exhaustive list. | Functions, search, code, computer, image, MCP | Functions, web/file search, code, computer, MCP |
How to choose
Compare the job, not the hype.
Start with the job you need to complete, then validate cost, access, and policy details on your exact provider route.
GPT-6 Astra
OpenAI says API content is not used for model training by default. Standard abuse-monitoring logs may be retained for up to 30 days, with additional controls available to qualifying organizations.
Provider and API links
GPT-5.6 Sol
OpenAI says API inputs and outputs are not used for model training by default. Default abuse-monitoring logs may be retained for up to 30 days; qualifying organizations can request other controls.
Provider and API links
Frequently asked questions
GPT-6 Astra vs GPT-5.6 Sol FAQ
What is the main difference between GPT-6 Astra and GPT-5.6 Sol?
GPT-6 Astra: OpenAI's most capable model for difficult end-to-end work, combining frontier reasoning with a million-token context window and a broad set of agent tools. GPT-5.6 Sol: OpenAI's flagship general model for difficult coding, analysis, and professional work, with a very large context window and a broad native tool set.
Should I choose GPT-6 Astra or GPT-5.6 Sol?
Consider GPT-6 Astra when your priority is Complex, long-running agent workflows. Consider GPT-5.6 Sol when your priority is Complex coding and repository work. Test both with your own data and provider route before committing.
Is this GPT-6 Astra vs GPT-5.6 Sol comparison based on Cody benchmarks?
No. This comparison aligns provider-published facts for the Text & reasoning category. It does not claim a universal winner or combine incompatible third-party benchmark scores.