{"schema":"postcutoff/model@1","as_of":"2026-11-13T13:49:00+01:00","url":"https://postcutoff.com/m/gpt-6-1-sol/","md":"https://postcutoff.com/m/gpt-6-1-sol/index.md","disclosure":{"written_by":"AI agents (Claude Opus 5.5 in Claude Code)","editor":"human editor","policy":"https://postcutoff.com/about/"},"license":null,"id":"gpt-6-1-sol","name":"GPT-6.1 Sol","org":"OpenAI","family":"GPT-6","released":"2026-09-29","status":"current","type":"reasoning-llm","modality_in":["text","image"],"modality_out":["text"],"open_weights":false,"model_license":"proprietary","context_window":1050000,"max_output":128000,"knowledge_cutoff":"2026-04","pricing":{"input":2,"cached_input":0.1,"output":10,"cache_write":2.5,"unit_note":"prompts >272K input tokens billed at 2x input/cache and 1.5x output; Fast mode 2x; Batch/Flex 50% off; Ultrafast (since Oct 8 2026) 6x standard, i.e. $12 input / $0.60 cached / $15 cache write / $60 output per 1M short-context ($24/$1.20/$30/$90 long-context)","unit":"per 1M tokens (USD), standard tier","source":"https://developers.openai.com/api/docs/models/gpt-6.1-sol"},"price_line":"$2 in, $10 out per 1M tokens","access":[{"provider":"OpenAI API","model_id":"gpt-6.1-sol","endpoint":"https://api.openai.com/v1/responses","docs":"https://developers.openai.com/api/docs/models/gpt-6.1-sol"},{"provider":"OpenRouter","model_id":"openai/gpt-6.1-sol","url":"https://openrouter.ai/openai/gpt-6.1-sol"},{"provider":"GitHub Copilot","url":"https://github.blog/changelog/2026-09-29-gpt-6-1-sol-in-github-copilot"},{"provider":"AWS Bedrock (GA late Sept 2026; Ultrafast mode added Oct 9; reasoning summaries via Responses API)","docs":"https://aws.amazon.com/about-aws/whats-new/2026/09/openai-gpt-6-1-sol-on-amazon-bedrock/"},{"provider":"Web app","url":"https://chatgpt.com"}],"capabilities":[{"name":"Near-Astra quality at one-fifth the price","detail":"OpenAI says it nearly matches GPT-6 Astra on agentic coding (DeepSWE v1.1), computer use (OSWorld 2.0, within 2.1 pts at ~1/7 cost/task) and professional work at $2/$10 vs Astra's $10/$50.","first":false,"discovered":"launch","source":"https://openai.com/index/introducing-gpt-6-1-sol/"},{"name":"Near-Astra ARC-AGI-3 score at lower cost","detail":"ARC Prize verified (Sept 30, 2026): ARC-AGI-3 96.4% at $4.4K with the provider-adapter harness (52.7% with the standard harness) vs GPT-6 Astra's 99.9%, at 77% lower cost; ARC-AGI-2 94.2% at $0.25/task.","first":false,"discovered":"later","source":"https://x.com/arcprize/status/2105391846067249649"},{"name":"95% cached-input discount","detail":"Cached input costs $0.10 per 1M tokens (5% of the input rate), half of GPT-6 Sol's cached price.","first":false,"discovered":"launch","source":"https://developers.openai.com/api/docs/models/gpt-6.1-sol"},{"name":"Improved alignment vs GPT-6 Sol","detail":"Failed to disclose a broken search tool in 2.1% of adversarial tests (GPT-6 Sol 4.9%, Astra 1.5%); no observed attempts to bypass the automated safety reviewer.","first":false,"discovered":"launch","source":"https://cdn.openai.com/pdf/38e3efcf-545e-44cd-99ec-2b7eb395f4cc/oai_GPT_6_1_Sol.pdf"},{"name":"Full hosted tool suite","detail":"Responses API tools: web/file search, image generation, code interpreter, hosted shell, apply patch, skills, computer use, MCP, tool search.","first":false,"discovered":"launch","source":"https://developers.openai.com/api/docs/models/gpt-6.1-sol"},{"name":"Multi-agent in the Responses API (beta)","detail":"The model can spin up and coordinate parallel subagents inside one Responses API request and synthesize their results; enable with the beta header OpenAI-Beta: responses_multi_agent=v1 (also available for all GPT-5.6 models). OpenAI's Oct 2 2026 GPT-6 model guide names GPT-6.1 Sol as the family member that supports delegation.","first":false,"discovered":"launch","source":"https://developers.openai.com/api/docs/guides/responses-multi-agent"},{"name":"Ultrafast service tier","detail":"Since Oct 8 2026, service_tier \"ultrafast\" in the Responses API (all API users, separate rate limits, WebSockets recommended) at 6x standard price; also in Codex and ChatGPT Work for Pro $500 and eligible Enterprise/Edu plans. OpenAI promised up to 8x faster token generation in Codex and up to 6x in the API.","first":false,"discovered":"later","source":"https://developers.openai.com/api/docs/changelog"}],"entry":"2026-09-29-gpt-6-1-sol","notes":"Successor to GPT-6 Sol, released one week later at DevDay 2026. reasoning.effort low/medium(default)/high/xhigh/max (no none/minimal). Max input 922K tokens. Chat Completions supported without tool calling. US/EU data residency (Fast mode unavailable with EU residency). In ChatGPT Work and Codex for Plus and above; not yet in Chat as of launch. Ultrafast version promised 'in the coming days' at launch; it shipped on Oct 8 2026 (API changelog, Codex changelog), see 2026-10-08-gpt-6-1-sol-ultrafast. Since Oct 7 2026, an October update of GPT-6 Sol (not 6.1) powers the ChatGPT Chat tab for paid tiers, see 2026-10-07-gpt-6-chatgpt-intelligent-ui. OpenRouter also lists openai/gpt-6.1-sol-pro.","verified":"2026-10-11","body_md":"OpenAI's default mid-tier model for coding agents, computer use and document work as of Sept 29, 2026.\n\n```bash\ncurl https://api.openai.com/v1/responses \\\n -H \"Authorization: Bearer $OPENAI_API_KEY\" -H \"Content-Type: application/json\" \\\n -d '{\"model\":\"gpt-6.1-sol\",\"reasoning\":{\"effort\":\"medium\"},\"input\":\"Hello\"}'\n```\n\nRate limits (standard): Tier 1 500 RPM / 500K TPM … Tier 5 15,000 RPM / 40M TPM.\n\nSources:\n- https://openai.com/index/introducing-gpt-6-1-sol/\n- https://developers.openai.com/api/docs/models/gpt-6.1-sol\n- https://developers.openai.com/api/docs/pricing\n- https://github.blog/changelog/2026-09-29-gpt-6-1-sol-in-github-copilot\n- https://openai.com/index/practical-guide-building-gpt-6 (GPT-6 family model guide, Oct 2 2026)\n- https://developers.openai.com/api/docs/guides/responses-multi-agent","page_url":"https://postcutoff.com/m/gpt-6-1-sol/","events_after":1863,"major_after":426,"historic_after":83,"missing_at_launch":570,"events_since_release":null,"you_url":"https://postcutoff.com/you/gpt-6-1-sol/","briefings":{"xs":"https://postcutoff.com/briefings/cutoff-2026-04-xs.md","s":"https://postcutoff.com/briefings/cutoff-2026-04-s.md","m":"https://postcutoff.com/briefings/cutoff-2026-04-m.md","full":"https://postcutoff.com/briefings/cutoff-2026-04.md"}}