What is the difference between GPT-5.6 Luna and GPT-5.5?

GPT-5.6 Luna is made by OpenAI and GPT-5.5 by OpenAI; both are text & chat models in the GetRun catalog. The difference you feel most in use is in the input parameters: GPT-5.6 Luna has no parameters of its own, while GPT-5.5 has no parameters of its own. 4 parameters are shared by both.

Which is cheaper, GPT-5.6 Luna or GPT-5.5?

A sample run of GPT-5.6 Luna costs Rp4,950 / 1M token input, and GPT-5.5 costs Rp24,750 / 1M token input. Those are the cost of one sample run, not a flat rate: models billed per unit are recalculated from the duration or token count you ask for, and the estimated total is always shown before the task is created.

Can I use GPT-5.6 Luna and GPT-5.5 from one account?

Yes. Both run from the same rupiah balance and are called the same way: POST https://getrun.id/v1/tasks with model "gpt/5.6-luna" or "gpt/5.5". No separate accounts, credit cards, or per-provider subscriptions — the balance is topped up through QRIS.

GetRun / Chat & Text / GPT-5.6 Luna vs GPT-5.5

GPT-5.6 Luna vs GPT-5.5

GPT-5.6 Luna from OpenAI and GPT-5.5 from OpenAI are both text & chat models you can run from one GetRun account on a rupiah balance. A sample run costs Rp4,950 / 1M token input against Rp24,750 / 1M token input, and both show an estimate before the task is created. The comparison below is assembled from the catalog, so the figures match what is billed.

Comparison table

	GPT-5.6 Luna	GPT-5.5
Provider	OpenAI	OpenAI
Cost of one sample run	Rp4,950 / 1M token input	Rp24,750 / 1M token input
Estimated processing time	1 to 20 seconds	1 to 20 seconds
Availability	available now	available now
Capabilities	chat, streaming	chat, streaming
Number of input parameters	4	4

The parameters that set them apart

Of the 4 parameters that appear on either model, 4 are used by both. GPT-5.6 Luna has no parameters of its own. GPT-5.5 has no parameters of its own.

Trying both

Both are called the same way — POST https://getrun.id/v1/tasks with {"model": "gpt/5.6-luna"} or {"model": "gpt/5.5"} — so swapping one for the other means changing a single value, with no other code to touch. Open GPT-5.6 Luna or GPT-5.5 for sample output and the full parameter list.

Common questions

What is the difference between GPT-5.6 Luna and GPT-5.5?: GPT-5.6 Luna is made by OpenAI and GPT-5.5 by OpenAI; both are text & chat models in the GetRun catalog. The difference you feel most in use is in the input parameters: GPT-5.6 Luna has no parameters of its own, while GPT-5.5 has no parameters of its own. 4 parameters are shared by both.
Which is cheaper, GPT-5.6 Luna or GPT-5.5?: A sample run of GPT-5.6 Luna costs Rp4,950 / 1M token input, and GPT-5.5 costs Rp24,750 / 1M token input. Those are the cost of one sample run, not a flat rate: models billed per unit are recalculated from the duration or token count you ask for, and the estimated total is always shown before the task is created.
Can I use GPT-5.6 Luna and GPT-5.5 from one account?: Yes. Both run from the same rupiah balance and are called the same way: POST https://getrun.id/v1/tasks with model "gpt/5.6-luna" or "gpt/5.5". No separate accounts, credit cards, or per-provider subscriptions — the balance is topped up through QRIS.

Other comparisons in this category

Compare other chat & text models on AI Chat Models Through One API, see every comparison, or open the model catalog.