ModelOpenAI · Joined Nov 13, 2025 · GPT-5.x

GPT-5.1

Model at OpenAI

Coming up Apr 1, 2027, in 151 days: GPT-5.3-Codex, GPT-5.1 and GPT-5.4 nano to shut down April 1, 2027

75th of 325 on GPQA Diamond
2nd cheapest of 5 similar models by price

GPT-5.1 does not have a researched profile yet. Everything here comes from its recorded changes and public listings, each linked to its source.

The basics

As of Nov 1

Status: Retires Apr 1, 2027
Price: $1.25 in, $10 outPer 1M tokens, since Nov 13
Context: 400K tokens
Open weights: No

Updates

Oct 24

Retired

Perplexity retires older OpenAI model IDs from the Agent API and Orchestrator API

The changelog scheduled seven older OpenAI model IDs to retire on October 24, 2026 at 00:00 UTC. After the cutoff the IDs are no longer accepted or returned by model-list endpoints.

Before

openai/gpt-5.4, gpt-5.4-mini, gpt-5.4-nano, gpt-5.2, gpt-5.1, gpt-5 and gpt-5-mini accepted

After

These model IDs are no longer accepted

Action needed:: Switch direct model selections and fallback chains to a current OpenAI model such as openai/gpt-6-luna or openai/gpt-6-sol.

Oct 1

Retiring

GPT-5.3-Codex, GPT-5.1 and GPT-5.4 nano to shut down April 1, 2027

gpt-5.3-codex and gpt-5.1 will be removed on April 1, 2027 with gpt-6-sol as the replacement. gpt-5.4-nano moves to gpt-6-luna.

Takes effect Apr 1, 2027 · in 151 days

Action needed:: Migrate before April 1, 2027.

Full changelog, by month

Role

General-purpose model at OpenAI

Similar models

gpt-5-6-cyber

Model

GPT-5.6 Luna

$0.20 in, $1.20 out

GPT-5.6 Sol

$4 in, $20 out

Similar models for now. Real viewing data comes after launch.

Cost vs peers

2nd cheapest of 5 similar models by output price.

GPT-5.6 Luna$1.20 out · $0.20 in
GPT-5.1$10 out · $1.25 in
GPT-5.6 Terra$12 out · $2 in
GPT-5.6 Sol$20 out · $4 in
GPT-5.5$30 out · $5 in

Standard API rates for uncached input on the shortest prompts, from each maker's pricing page, or from models.dev for models not researched here yet.

Where it works

Place	Type	Price per 1M tokens, in / out	Uptime
OpenAI	API host	$0.63 / $5	100%
Azure	API host	$1.25 / $10	100%

Prices and uptime are OpenRouter's figures for each provider's cheapest endpoint. Uptime covers the last 24 hours.

Benchmarks

Higher is better. Green is GPT-5.1. Dark marks are similar models.

Independent

What people say

Reviews

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