Is gpt-5.6-terra cheaper than o4-mini?

No. The labeled example monthly cost is $19.8 for the old model and $44 for the replacement.

Does gpt-5.6-terra have a bigger context window than o4-mini?

Yes. The context window changes from 200,000 to 1,050,000 tokens.

| (o4-mini) to gpt-5.6-terra: price, context, and code

The official replacement is gpt-5.6-terra. | (o4-mini) shuts down on 2026-10-23 per OpenAI's deprecation page (checked 2026-10-17). On the labeled example of 10 million input tokens and 2 million output tokens, gpt-5.6-terra costs $44 a month, higher than $19.8 for o4-mini.

| (o4-mini) to gpt-5.6-terra

All values from official sources Checked 2026-10-17.

Price per 1M tokens

Price comparison. Example monthly cost for 10M input tokens and 2M output tokens. Labeled example, not a bill.
Field	Old	New	Change
Input	$1.1	$2	+81.8% (higher)
Output	$4.4	$12	+172.7% (higher)
Cached input	$0.275	$0.2	Not published
Example monthly cost	$19.8	$44	Example only

Context and max output

Token limits
Limit	Old	New	Change
Context window	200,000	1,050,000	+425% (higher)
Max output	100,000	128,000	+28% (higher)

Capabilities that differ

No differing capability values are published for both models.

API changes

No parameter change is listed on the official pages we checked. The sample below only swaps the model id.

Code

python typescript curl

python before

from openai import OpenAI
client = OpenAI()
response = client.chat.completions.create(
    model="o4-mini",
    messages=[{"role": "user", "content": "Hello"}],
)

python after

from openai import OpenAI
client = OpenAI()
response = client.chat.completions.create(
    model="gpt-5.6-terra",
    messages=[{"role": "user", "content": "Hello"}],
)

typescript before

import OpenAI from "openai";
const client = new OpenAI();
const response = await client.chat.completions.create({
  model: "o4-mini",
  messages: [{ role: "user", content: "Hello" }],
});

typescript after

import OpenAI from "openai";
const client = new OpenAI();
const response = await client.chat.completions.create({
  model: "gpt-5.6-terra",
  messages: [{ role: "user", content: "Hello" }],
});

curl before

curl https://api.openai.com/v1/chat/completions \
  -H "Authorization: Bearer $OPENAI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"o4-mini","messages":[{"role":"user","content":"Hello"}]}'

curl after

curl https://api.openai.com/v1/chat/completions \
  -H "Authorization: Bearer $OPENAI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"gpt-5.6-terra","messages":[{"role":"user","content":"Hello"}]}'

Checklist

Read the shutdown date for o4-mini on the linked official page.
Point your requests at gpt-5.6-terra.
Re-check price, context, and parameters on the provider pages linked here.
Ship the change before the published shutdown date.

Replacement for | (o4-mini): what changes when you switch