Flow - 4x faster than typing
Mini toolsGPT 5.1 Instant
By OpenAI
Model family: GPT
Built on the GPT-5 system, Instant is tuned for quick, natural replies while keeping production features like tool calls, streaming, and schema-true JSON. In ChatGPT and the API, the unified router sends typical prompts to the fast model and reserves the deeper tier for harder problems. Recent release notes highlight upgrades to Instant on safety-sensitive queries and automatic routing for quicker, helpful answers.
Multimodal
Overview
The Instant variant is the fast, chat-first option in the 5.1 line. It favors low latency and solid instruction following, with long context, function calling, and reliable JSON. For most everyday prompts, the system router selects Instant by default.
About OpenAI
OpenAI is a technology company that specializes in artificial intelligence research and innovation.
Industry:
Artificial Intelligence
Company Size:
4500
Location:
San Francisco, California, US
Website:
openai.com
Tools using GPT 5.1 Instant
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ChatGPT — v61.5M+ context window points to much longer context handling across documents, codebases, and persistent sessions. A new pre-training foundation suggests a deeper base-model reset rather than a small iterative checkpoint. Rumored 10T-scale training implies broader capability coverage and stronger knowledge compression. Substantial agentic gains point to better tool use, task planning, and multi-step execution. Stronger reasoning aimed above current top tiers implies better performance on difficult chained problem-solving tasks.
Last updated: April 6, 2026
