Is gpt-5.6-sol cheaper than gpt-5.3-chat-latest?

No. The labeled example monthly cost is $45.5 for the old model and $80 for the replacement.

Does gpt-5.6-sol have a bigger context window than gpt-5.3-chat-latest?

Yes. The context window changes from 128,000 to 1,050,000 tokens.

gpt-5.3-chat-latest to gpt-5.6-sol: price, context, and code

The official replacement is gpt-5.6-sol. gpt-5.3-chat-latest shut down on 2026-08-10 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-sol costs $80 a month, higher than $45.5 for gpt-5.3-chat-latest.

gpt-5.3-chat-latest to gpt-5.6-sol

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	$1.75	$4	+128.6% (higher)
Output	$14	$20	+42.9% (higher)
Cached input	$0.175	$0.4	Not published
Example monthly cost	$45.5	$80	Example only

Context and max output

Token limits
Limit	Old	New	Change
Context window	128,000	1,050,000	+720.3% (higher)
Max output	16,384	128,000	+681.3% (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="gpt-5.3-chat-latest",
    messages=[{"role": "user", "content": "Hello"}],
)

python after

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

typescript before

import OpenAI from "openai";
const client = new OpenAI();
const response = await client.chat.completions.create({
  model: "gpt-5.3-chat-latest",
  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-sol",
  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":"gpt-5.3-chat-latest","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-sol","messages":[{"role":"user","content":"Hello"}]}'

Checklist

Read the shutdown date for gpt-5.3-chat-latest on the linked official page.
Point your requests at gpt-5.6-sol.
Re-check price, context, and parameters on the provider pages linked here.
Ship the change before the published shutdown date.

Replacement for gpt-5.3-chat-latest: what changes when you switch