How much does GPT-5.5 Pro cost per million tokens?

GPT-5.5 Pro costs $30 per million input tokens and $180 per million output tokens at list price.

What is the context window of GPT-5.5 Pro?

GPT-5.5 Pro accepts up to 1,050,000 tokens of context and returns up to 128,000 output tokens.

How much do 1,000 chat messages cost with GPT-5.5 Pro?

About $120.00, assuming 1,000 input + 500 output tokens per message.

Is there a cheaper alternative to GPT-5.5 Pro?

In the same price range, Anthropic Claude Sonnet 5.5 ($2 / $10), Z.ai GLM 5.3 Prime ($2.80 / $8.80), Qwen Qwen3.8 Max Prime ($4 / $12) cost less per token. Quality differs: test on your own prompts.

Where can I buy OpenAI API credits for less?

Discount credit books resell OpenRouter usage below face value within their depth, OpenRouter adds a 5.5% card fee, and OpenAI sells its own credits at face value. The live table on this page ranks them for $100 of usage.

OpenAI · live price

GPT-5.5 Pro API pricing

GPT-5.5 Pro is OpenAI’s high-capability model optimized for deep reasoning and accuracy on complex, high-stakes workloads. It features a 1M+ token context window (922K input, 128K output) with support for...

Frontier (blended $5+ per 1M)Tool callingReasoningfile inputimage input

Input: $30; per 1M tokens
Output: $180; per 1M tokens
Cached input: –; per 1M tokens
Context: 1.1M; 128K max output

List price from OpenRouter, which passes OpenAI's price through without markup. Refreshed hourly. Released April 24, 2026. Model id openai/gpt-5.5-pro.

What GPT-5.5 Pro costs in practice

At list price, before any batch or caching discount.

1,000 chat messages

$120.00

1,000 input + 500 output tokens each

1,000 RAG questions

$330.00

8,000 input + 500 output tokens each

100 coding-agent steps

$126.00

30,000 input + 2,000 output tokens each, no caching

GPT-5.5 Pro price history

No price change since we started tracking on 2026-10-01. We record prices daily; changes will show here.

GPT-5.5 Pro price by host

One host serves this model through OpenRouter.

OpenAI$15 in · $90 out · 1.1M ctx

Where to buy OpenAI credits for less

GPT-5.5 Pro costs the same per token everywhere it's sold through OpenRouter. What changes is the price of the credits. Live quotes for $100 of usage:

#	Where you buy	You payYou pay for $100.00 of usage	vs list price	Price source
1	OrbioCardCheapest right now Credits from a discount book, plus a 5% platform fee and card processing, both included in the quote.	$85.10 incl. $2.60 card processing	-14.9%	live quote
2	smaaartCard Credits from a discount book, plus a 5% platform fee on face value. Card processing and taxes shown at checkout.	$95.00 + card processing and tax at checkout (not in this number)	-5.0%	live quote
3	Direct from the labCard Prepaid credits at face value (OpenAI, Anthropic, Google…). Taxes may apply.	$100.00 no top-up fee	list price	face value
4	OpenRouterCrypto 5% on crypto purchases. No markup on model prices.	$105.00 fees included	+5.0%	published fee
5	OpenRouterCard 5.5% on card purchases, $0.80 minimum. No markup on model prices.	$105.50 fees included	+5.5%	published fee

Disclosure: this site is run by the team behind smaaart, one of the options compared. Tables are ranked by price only, from live quotes and published fees, including when smaaart isn't first. How we compare

GPT-5.5 Pro cost calculator

Enter your monthly tokens to price your own usage.

Model$30.00 in / $180.00 out per 1M tokens · list price, liveInput tokens / month (millions)Output tokens / month (millions)

Usage at list price$3,300.00/ month

Cheaper alternatives to GPT-5.5 Pro

Other labs' models in the same price range or the one below, cheaper per token.

Model	Input / 1M	Output / 1M	Blended 3:1	Context
Anthropic: Claude Sonnet 5.5	$2	$10	$4	1M
Z.ai: GLM 5.3 Prime	$2.80	$8.80	$4.30	1M
Qwen: Qwen3.8 Max Prime	$4	$12	$6	1M
Anthropic: Claude Opus 5.5	$4	$20	$8	1M
SpaceXAI: Grok 4.7	$2	$6	$3	500K
Qwen: Qwen3.8 Max (0902)	$2	$6	$3	1M

Other OpenAI models

Model	Input / 1M	Output / 1M	Blended 3:1	Context
GPT-5.5	$5	$30	$11.25	1.1M
GPT-5.4 Image 2	$8	$15	$9.75	272K
GPT Chat Latest	$5	$30	$11.25	400K
GPT-5.4 Nano	$0.2	$1.25	$0.463	400K
GPT-5.4 Mini	$0.75	$4.50	$1.69	400K
GPT-5.4 Pro	$30	$180	$67.50	1.1M

All OpenAI API prices