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MODEL SIGNAL · OPENAI

GPT-6.1 Sol

GPT-6.1 Sol is a cost-effective model from OpenAI designed to deliver near-flagship performance for coding, computer use, and professional tasks.

CATEGORYGeneral
CONTEXT1M tokens
RELEASEDSeptember 22, 2026
Key Features
  • 1M token context window
  • Optimized for coding and agentic computer use
  • Priced at 20% of the cost of OpenAI's flagship Astra model API

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MODEL SIGNAL

GPT-6.1 Sol

OpenAI's high-context, aggressively discounted workhorse positioned just below the flagship Astra.

Bottom line

OpenAI has released GPT-6.1 Sol, explicitly targeting the tier immediately below their flagship GPT-6 Astra. With a massive 1.05-million-token context window, an unusually large 128,000-token output limit, and a deeply discounted prompt-caching pricing structure, the model is engineered for agentic coding, computer use, and heavy professional workflows. The operator read is clear: this is designed to be the high-volume engine for complex, iterative tasks where Astra's premium cost is prohibitive.

Signal

The strongest signal here is the structural shift in API pricing and output limits to support agentic workflows. Standard input tokens are priced at $2 per million, but cached input tokens drop to an aggressive $0.10 per million. Paired with a 128,000-token maximum output window, this configuration natively supports continuous, loop-based interactions over massive static contexts (like full codebases or document repositories) while allowing the model to generate highly extensive artifacts in a single pass.

Noise

OpenAI’s claim of "near-Astra performance" is a provider benchmark that requires rigorous field validation. What "near" means across varying workloads—creative generation versus strict coding or reasoning—remains unproven. Additionally, while the model is listed as multimodal in routing catalogs, the primary verified specs focus on computer use and professional work; operators should wait for explicit modality performance validations before assuming parity with dedicated vision or audio models.

Model profile

Based on verified OpenAI API documentation and release announcements from September 30, 2026:

  • Context window: 1,050,000 tokens.
  • Maximum output: 128,000 tokens.
  • Standard Pricing: $2 per million input tokens, $0.10 per million cached input tokens, and $10 per million output tokens.
  • Target Workloads: Complex coding, computer use automation, and professional work.

Assessment

GPT-6.1 Sol represents a deliberate segmentation in OpenAI's GPT-6 generation. By offloading heavy, repetitive context tasks to a cheaper "Sol" tier, OpenAI is acknowledging that agentic systems require a different economic model than zero-shot chatbot interactions. The 95% discount on cached inputs is not just a price cut; it is a structural incentive designed to change how developers build stateful applications.

Where it fits

This model is purpose-built for environments that demand massive context retention and long generation loops. It is a direct fit for agentic coding environments where a system must continually read a large repository and output substantial code rewrites. It also fits document-heavy professional workflows—such as legal or financial analysis—and computer-use automation where the model needs an extensive history of user interface states to execute tasks reliably.

Operator implications

The emerging pattern suggests developers must fundamentally re-architect their system prompts and API call structures. To capitalize on the $0.10/M cached token pricing, operators should front-load massive context blocks (reference libraries, static code, exhaustive system instructions) and keep them warm, iterating rapidly with small variable inputs. Applications failing to utilize the caching mechanism will be burning unnecessary capital.

Launch-day pulse

Telemetry snapshots from OpenRouter confirm that third-party routing adapters are live and recognizing the model as available. However, operators should treat launch-window telemetry purely as a signal of availability; actual throughput, latency, and cache-hit reliability under peak global load for a 1M-context model will remain volatile in the immediate post-release window.

Model Signal · Signal + Noise · Isaiah Steinfeld