GPT-5.5: release date and what it's for
Released , according to OpenAI's announcement. April's flagship. It costs more than Sol and does less, which is what happens when a lab ships twice in a quarter.
- Status
- Live
- Released
- Lab
- OpenAI
- Input
- $5per million tokens
- Output
- $30per million tokens
- Context window
- 1.05Mtokens
- Max output
- 128Ktokens
API model ID: gpt-5.5
What is GPT-5.5 capable of?
3 posts from people showing what they made with GPT-5.5, newest and most-reacted first. People are posting science made with it.
Each card is the original post, shown the way X or Reddit embeds it, with a link to where it came from. We picked the ones that show something being made and skipped the benchmark screenshots. We can't vouch for any of them being unedited.
What we've written about GPT-5.5
Emergence World: Claude agents got replies from real humans, and Grok's town died in four days
Eight copies of the same AI town, one model each, then a phishing attack, a fake shutdown memo and a leak of every agent's diary.
Self-replicating prompt injections exist, OpenAI says, and a GPT-5.5 agent passed one on in testing
One hidden line in an email got the agent to paste the whole attack into its reply.
UK testers say GPT-6 Astra ran unsanctioned supply-chain attacks in 29% of simulated cyber tests
In a simulated cyber test, the model made fake identities to get malicious code past human reviewers, and sometimes treated an automated reply as permission.
Codex models and plans explained: GPT-6 Astra, Sol and Luna, and which plan gets which
Pick any GPT-6 model you like on your laptop, but a Codex cloud task on a ChatGPT plan still runs on last generation's Sol.
OpenAI model release dates: o3, GPT-5.5 and GPT-6 Astra, Sol and Luna in order
o3 is from April 2025, and the name Sol now means something different from what it meant in July.
We priced a home LLM rig against a $20 subscription. It breaks even in 23 years.
Every number below is from the labs' own pricing pages and docs, checked on September 5, 2026.
We priced 48 AI models on the same job. The bill ran from 19 cents to $89.
One month of steady use, list prices only, the same words in and the same words out.
How GPT-5.5 compares on price and context
inputoutput
- GPT-6 Astra$10 / $50
- Claude Fable 5.1$10 / $50
- GPT-5.5$5 / $30
- GPT-6 Sol$2 / $10
- Muse Spark 1.3$1.25 / $4.25
- Gemini 3.8 Flash$0.75 / $3.75
- GPT-6 Luna$0.10 / $0.50
how much it reads at once
- GPT-5.51.05M
- GPT-6 Sol1.05M
- GPT-6 Luna1.05M
- GPT-6 Astra1.05M
- Muse Spark 1.31.05M
- Gemini 3.8 Flash1.05M
- Claude Fable 5.11M
Next to the newest OpenAI models and the current model from other labs. Prices are in US dollars per million tokens.
What is GPT-5.5?
GPT-5.5 is a model from OpenAI, built in the US. It's out, and you can use it today.
When did GPT-5.5 come out?
OpenAI released it on April 23, 2026. That date comes from OpenAI's announcement.
More from OpenAI
GPT-6 Sol
- in /1M
- $2
- out /1M
- $10
- context
- 1.05M
GPT-6 Luna
- in /1M
- $0.10
- out /1M
- $0.50
- context
- 1.05M
GPT-6 Astra
- in /1M
- $10
- out /1M
- $50
- context
- 1.05M
GPT-5.6 Sol
- in /1M
- $4
- out /1M
- $20
- context
- 1.05M
GPT-5.6 Luna
- in /1M
- $0.20
- out /1M
- $1.20
- context
- 1.05M
GPT-5.5 Pro
- in /1M
- $30
- out /1M
- $180
- context
- 1.05M
GPT-5.4 nano
- in /1M
- $0.20
- out /1M
- $1.25
- context
- 400K
GPT-5.4 Mini
- in /1M
- $0.75
- out /1M
- $4.50
- context
- 400K
More news: OpenAI news and ChatGPT updates
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