Model · Multimodal language model
GPT-5.5 Instant
The low-latency GPT-5.5 tier that became ChatGPT's default model, served through OpenAI's managed developer API only as the rotating chat-latest alias and as dated preview deployments on Azure Foundry, without downloadable model weights or a pinnable first-party snapshot.
- Developer
- OpenAI
- Distribution
- Developer API · Third-party hosting
- Artifact licensing
- Proprietary access
- License scope
- Reviewed release artifacts and mandatory terms; not an assessment of training code or training data openness.
- Licenses
- OpenAI Services Agreement
- Boundary
- This record represents the GPT-5.5 Instant release of May 5, 2026, exposed on the first-party API only as the moving chat-latest alias with no documented fixed snapshot: the alias page lists chat-latest as both model ID and sole snapshot and states the underlying snapshot is regularly updated. Azure Foundry hosts the same line as dated gpt-chat-latest preview deployments naming GPT-5.5 Instant as the OpenAI-side equivalent. The base GPT-5.5 release, GPT-5.5 Pro, the invite-only Cyber preview, ChatGPT application behaviors, Codex, the GPT-5.3 Instant predecessor, fine-tuned derivatives, and later Instant generations are separate service, application, or model boundaries.
Risk statements
“High Capability” · Precautionary
GPT-5.5 Instant is our first Instant model to be treated as High Capability in the Biological and Chemical domain, as well as in the Cybersecurity domain. As such, we have applied biological and chemical, and cybersecurity, safeguards to this deployment.
- Risk areas
- Biological or chemical · Cyber
- Covers
- The model itself
Read the developer's statement ↗ · 2026-10-09 · Research confidence: High
OpenAI names this release against “High Capability” in biological or chemical and cyber capability, as a precaution. The statement covers the model itself. This is the developer's own statement, not an Atlas risk rating.
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