Open ChatGPT and sign in.
Use the official ChatGPT website or app. Confirm you are in the correct personal or workspace account.
Setup in six steps.
Interface labels can change. The workflow stays the same: sign in, start clean, select the model, check the tier, test, then verify.
Start a new chat.
A fresh chat avoids old instructions and attachments affecting your test.
Open the model picker.
Look near the top of the conversation for the current model name or model menu.
Select GPT-5.6.
If tiers are shown, start with Terra. Choose Sol only when the task needs deeper judgment. Choose Luna for low-risk volume.
Run the first test prompt.
Give it one small, checkable task. Do not start with your entire business or a sensitive workflow.
Verify the output.
Check names, dates, numbers, links, and assumptions against the original source before you act.
Copy and paste
Your first clean test.
I am testing GPT-5.6 for a small, checkable task. Task: Turn the notes below into a five-step checklist. Rules: 1. Use only the notes I provide. 2. Mark missing information as [NEEDS INPUT]. 3. Do not invent names, numbers, dates, prices, or links. 4. End with a short verification list. Notes: [paste a short set of non-sensitive notes]
Choose the tier after the task.
Do not choose Sol because it sounds premium. Choose based on consequence, complexity, volume, and how easily you can check the result.
Hard to reverse
Final strategy, difficult architecture, sensitive language, or complex analysis.
Most daily work
Drafting, coding, planning, research synthesis, and routine decisions.
High volume
Extraction, tagging, formatting, classification, and simple rewrites.
If GPT-5.6 does not appear.
Work through these checks in order. Do not install browser extensions or enter credentials into unofficial tools.
Check the account and plan
Make sure the account you opened is the one with the expected ChatGPT access.
Start a fresh conversation
Some older chats can stay attached to an earlier model or mode.
Update the official app
If you use iOS, Android, macOS, or Windows, install the current official update.
Wait for rollout
New model availability can arrive gradually. Check OpenAI's official release page and help center.
Safety checkpoint
Model access is not an approval to share private data.
Remove passwords, API keys, private customer information, medical details, legal documents, bank information, and employer-confidential material unless you have a clear approved policy for that data.
Continue the cluster