OpenAI flagship model
GPT-6 Astra
OpenAI's most capable model for demanding end-to-end professional work, including complex reasoning, coding, computer use, research, and document creation.
- Context window
- 1.05M
- tokens
- Max output
- 128K
- tokens
- Input
- $10.00
- per 1M tokens
- Cached input
- $1.00
- per 1M tokens
- Output
- $50.00
- per 1M tokens
01 / Overview
What GPT-6 Astra Is
GPT-6 Astra is OpenAI's most capable general-purpose model for demanding professional work, designed for workloads where the quality of reasoning and execution is more important than minimizing the cost of each individual request.
A Capability-First Model for End-to-End Work
OpenAI positions Astra for complex reasoning, coding, computer use, research, and document creation. That scope is important: the model is not limited to producing a strong answer from a single prompt. It is intended for workflows where the model may need to understand a large working set, reason across multiple constraints, interact with tools, inspect intermediate results, and continue toward a complete outcome.
For application teams, Astra is therefore most interesting at the difficult end of the model-selection spectrum. It can be evaluated for tasks that are expensive to get wrong, hard to decompose into simple calls, or require several capabilities in one workflow.
Its higher API price means the model should not automatically become the default for every request. A better strategy is to identify the workloads where stronger reasoning, better coding performance, computer interaction, or richer synthesis can materially reduce retries, human review, or workflow failure.
- OpenAI's most capable model for the most demanding work.
- Designed for complex reasoning, coding, computer use, research, and document creation.
- Supports a 1.05M-token context window for large working sets.
- Offers configurable reasoning from
lowthroughmax. - Supports rich tool-based workflows through the Responses API.
- Provider
- OpenAI
- Family
- GPT-6
- Tier
- Flagship / Most capable
- Knowledge cutoff
- Apr 30, 2026
- Input modalities
- Text, Image
- Output modality
- Text
- Reasoning effort
- Low → Max
02 / Use cases
Where GPT-6 Astra Is Most Valuable
Astra is best evaluated on workloads where complexity accumulates across reasoning, context, tools, and execution rather than on simple prompts that a cheaper model can already solve reliably.
Use Astra Where Failure Is Expensive
The strongest use case for a capability-first model is not "anything important." It is work where mistakes or shallow reasoning create meaningful downstream cost.
In software engineering, that might mean understanding a large codebase before proposing a migration or fixing a difficult bug. In research, it may require reconciling evidence from multiple sources before producing a defensible synthesis. In computer-use workflows, the model must interpret an interface, decide what to do next, and recover when the environment does not behave exactly as expected.
Document creation is another relevant category. Producing a useful specification, report, analysis, or technical plan often requires maintaining consistency across many requirements rather than generating isolated paragraphs.
Astra should be tested on the hardest representative cases from the actual product workload. If the quality advantage appears only on rare edge cases, routing those cases selectively may be more economical than sending all traffic to the model.
- Complex professional reasoning with multiple interacting constraints.
- Coding and software-engineering tasks that require broad project understanding.
- Computer-use workflows that combine observation, decision-making, and action.
- Research tasks requiring synthesis across large or heterogeneous sources.
- Long-form document creation where structure and consistency matter.
- 01
Complex reasoning
Work through multi-step problems, competing constraints, and decisions that require deeper analysis.
- 02
Software engineering
Handle difficult coding, debugging, architecture, migration, and codebase-level technical tasks.
- 03
Computer use
Interpret interfaces and carry out multi-step computer workflows using supported tool capabilities.
- 04
Research and documents
Synthesize evidence, organize large working sets, and create substantial professional deliverables.
03 / Pricing
GPT-6 Astra Pricing
GPT-6 Astra is priced as a capability-first model: $10.00 per million standard input tokens, $1.00 per million cached input tokens, $12.50 per million cache-write tokens, and $50.00 per million output tokens.
Measure the Cost of Completing the Work
At Astra's price level, cost analysis should go beyond the headline rate. Long prompts, extended outputs, repeated tool calls, and high reasoning settings can all influence the economics of a production workflow.
The relevant comparison is often cost per completed outcome. If Astra solves a complex task in one run while a cheaper model requires multiple retries, more validation, or manual correction, the difference in effective cost can be smaller than the token prices imply. The reverse is also true: if a lower-cost model consistently meets the required quality threshold, using Astra adds expense without enough practical benefit.
Prompt caching can be especially relevant for applications with a large stable prefix, such as repeated system instructions or shared background context. OpenAI separately lists cache-write pricing, which should be included when estimating the full lifecycle of cached prompts.
- $10.00 per 1M standard input tokens.
- $1.00 per 1M cached input tokens.
- $12.50 per 1M cache-write tokens.
- $50.00 per 1M output tokens.
- Tool-specific operations may introduce additional charges.
1M tokens · USD
- Input
- $10.00
- Cached input
- $1.00
- Cache writes
- $12.50
- Output
- $50.00
Example: 10K input + 2K output
- Input cost
- $0.1000
- Output cost
- $0.1000
- Estimated total
- $0.2000
04 / Context
A 1.05M-Token Context for Large Professional Working Sets
GPT-6 Astra provides a 1,050,000-token context window and supports up to 128,000 output tokens, creating room for extensive source material, instructions, project state, and intermediate tool results.
The Window Is a Working Set, Not a Target
A million-token context window changes what developers can place in a single model interaction, but it does not remove the need for context engineering.
For a complex coding task, the working set may contain repository files, architecture notes, issue history, logs, and implementation constraints. A research workflow may combine papers, web results, internal documents, and prior analysis. A computer-use task may accumulate screenshots, state, and tool feedback as the workflow progresses.
Astra can accommodate much larger working sets than traditional short-context models, but relevance still matters. Unnecessary data increases both cost and cognitive noise. The goal should be to supply enough context to preserve important relationships without treating the full window as storage that must be filled.
This distinction becomes financially important above 272K input tokens because OpenAI applies higher long-context pricing to the entire request.
- 1,050,000-token context window.
- Maximum output of 128,000 tokens.
- Useful for codebase-scale, research-heavy, and document-intensive workloads.
- Large context should be measured for relevance as well as capacity.
- Requests above 272K input tokens use higher pricing multipliers.
Context window
1,050,000
Max output
128,000
Astra's working context can include system instructions, documents, code, retrieved evidence, conversation state, tool results, and the current task.
05 / Reasoning
Reasoning Levels for Difficult Tasks
GPT-6 Astra supports low, medium, high, xhigh, and max reasoning effort, allowing applications to adjust reasoning depth to the difficulty and value of a task.
Do Not Treat Max as the Default Answer
Astra is designed for demanding reasoning, but the strongest reasoning setting is not automatically the most efficient configuration for every request.
A well-scoped coding change, structured analysis, or clear document transformation may perform well at a lower setting. Difficult debugging, research synthesis, architectural decisions, or computer-use workflows with uncertain state may justify testing higher levels.
For production evaluation, each reasoning level should be treated as a model configuration rather than a cosmetic parameter. Measure whether increasing effort changes task success, output quality, latency, and token consumption enough to justify the difference.
A representative test set should include routine tasks as well as the difficult cases that motivated considering Astra in the first place.
Well-scoped professional task
Start by testing lower reasoning levels when the requirements and expected output are already clear.
Hard end-to-end task
Test higher effort for difficult coding, research, planning, computer use, and multi-constraint reasoning.
06 / Capabilities
Tools for End-to-End AI Workflows
Astra combines text and image input with streaming, function calling, structured outputs, and a broad Responses API toolset that can extend a model run beyond pure text generation.
From Reasoning to Action
OpenAI lists web search, file search, image generation, code interpreter, hosted shell, Apply Patch, Skills, computer use, MCP, and Tool Search as supported tools for GPT-6 Astra in the Responses API.
This combination is important for the model's positioning. A research task can search for information and work with files. A coding workflow can reason about code and use execution or patching tools. A computer-use workflow can interact with graphical interfaces. MCP and Tool Search can connect the model to a broader set of external capabilities.
Function calling and structured outputs make it easier to integrate these workflows into application-controlled systems rather than relying on unstructured prose alone.
The model supports text input and output plus image input. Direct audio and video modalities are not supported on the model card. Fine-tuning is also currently listed as unsupported.
- Text input and output.
- Image input for vision-based tasks.
- Streaming responses.
- Function calling and structured outputs.
- Web search and file search.
- Image generation and code interpreter.
- Hosted shell and Apply Patch.
- Skills, computer use, MCP, and Tool Search.
- Fine-tuning is currently not supported.
- Supported
Text and vision
Accept text and image input and generate text output.
- Supported
Structured integration
Use function calling and structured outputs for application-controlled results.
- Supported
Research tools
Use web search and file search as part of a Responses API workflow.
- Supported
Code execution
Use code interpreter, hosted shell, and Apply Patch for technical workflows.
- Supported
Computer use
Use computer interaction for tasks that require working through graphical interfaces.
- Supported
Extensible tools
Use Skills, MCP, Tool Search, image generation, and other supported Responses API tools.
07 / Evaluation
Strengths and Limitations
GPT-6 Astra is designed to maximize capability on demanding work, which makes it most valuable when a workload can actually benefit from deeper reasoning, broader tool use, or stronger end-to-end execution.
Strengths
Highest-capability positioning
OpenAI identifies Astra as its most capable model for the most demanding work.
End-to-end workflow fit
Reasoning, coding, computer use, research, and document creation can be combined with a broad toolset.
Large working context
A 1.05M-token context window supports substantial codebases, documents, evidence, instructions, and workflow state.
Deep reasoning controls
Reasoning can be configured from low through max to match the difficulty and value of a specific task.
What to consider
Premium inference cost
At $10 per 1M standard input tokens and $50 per 1M output tokens, Astra should be reserved for workloads where its capability produces measurable value.
Long-context pricing increases
Requests above 272K input tokens use higher input, cache, and output pricing multipliers for the entire request.
No fine-tuning
The current OpenAI model documentation lists fine-tuning as unsupported for GPT-6 Astra.
Simpler workloads may not need Astra
If a less expensive model consistently meets the required quality threshold, routing routine traffic to Astra can increase cost without improving the product outcome.
Evaluate capability, not reputation
Test GPT-6 Astra on your hardest real-world tasks
Run representative production prompts with your actual context and tools, then measure response quality, token usage, request cost, and context consumption before selecting Astra for a workflow.
Start FreeConnect your own OpenAI API key and evaluate GPT-6 Astra under the same prompt, context, and reasoning conditions your application will use.
Common Questions
What is GPT-6 Astra?
GPT-6 Astra is OpenAI's most capable model for demanding professional work. OpenAI recommends it for complex reasoning, coding, computer use, research, and document creation.
How much does GPT-6 Astra cost?
Standard text-token pricing is $10.00 per 1M input tokens, $1.00 per 1M cached input tokens, $12.50 per 1M cache-write tokens, and $50.00 per 1M output tokens. Tool-specific charges may apply separately.
What is the context window of GPT-6 Astra?
GPT-6 Astra has a 1,050,000-token context window and supports up to 128,000 output tokens.
What reasoning levels does GPT-6 Astra support?
GPT-6 Astra supports low, medium, high, xhigh, and max reasoning effort.
What is the knowledge cutoff for GPT-6 Astra?
OpenAI lists April 30, 2026 as the knowledge cutoff for GPT-6 Astra.
Does GPT-6 Astra support image input?
Yes. GPT-6 Astra supports text and image input and produces text output. Direct audio and video modalities are not supported according to the current model card.
What tools does GPT-6 Astra support?
OpenAI currently lists web search, file search, image generation, code interpreter, hosted shell, Apply Patch, Skills, computer use, MCP, and Tool Search as supported Responses API tools.
Is GPT-6 Astra suitable for coding?
Yes. OpenAI explicitly recommends GPT-6 Astra for coding, and its supported tools include code interpreter, hosted shell, and Apply Patch for technical workflows.
When should an application use GPT-6 Astra?
Astra is most relevant for difficult, high-value tasks where deeper reasoning, complex coding, research synthesis, computer use, large context, or multi-step tool execution can justify a higher inference cost.
Can GPT-6 Astra be fine-tuned?
No. The current OpenAI model documentation lists fine-tuning as unsupported for GPT-6 Astra.
Model information
Last updated
The specifications and prices on this page are based on the official OpenAI documentation for GPT-6 Astra. Provider pricing, model limits, supported tools, endpoints, and availability may change, so production assumptions should be checked against the latest provider documentation.