Which is cheaper, GPT-5.4 mini or GPT-5.5?

GPT-5.4 mini. On a task of 1,500 input and 500 output tokens across 3 calls, GPT-5.4 mini costs $0.01013 per task against $0.06750 for GPT-5.5, which makes it 6.67x cheaper (a 85% saving).

How much do GPT-5.4 mini and GPT-5.5 charge per million tokens?

GPT-5.4 mini: $0.75 per million input tokens and $4.5 per million output tokens. GPT-5.5: $5 input and $30 output. These are published list rates as of August 2026, excluding cached, batch and long-context tiers.

What does a million tasks cost on GPT-5.4 mini vs GPT-5.5?

At the same fixed profile, one million tasks cost $10,125 on GPT-5.4 mini and $67,500 on GPT-5.5. The gap comes entirely from list-price differences, not from any difference in the work done.

Model price comparisons · August 2026

GPT-5.4 mini vs GPT-5.5: API pricing compared

Same task, same tokens, two invoices. Every figure on this page is computed from our open pricing dataset, not copied from a blog post.

GPT-5.4 mini is 6.67x cheaper than GPT-5.5 on a realistic task profile of 1,500 input and 500 output tokens per call, 3 calls per task: $0.01013 against $0.06750 per task, a 85% saving on identical work. Run a million tasks a month and that is the difference between $10,125 and $67,500.

Model	Input $/1M tok	Output $/1M tok	Output multiple	$/task	$/1M tasks
GPT-5.4 miniOpenAI · mid	$0.75	$4.5	6x	$0.01013	$10,125
GPT-5.5OpenAI · frontier	$5	$30	6x	$0.06750	$67,500

Monthly bill at three volumes

Tasks / month	GPT-5.4 mini	GPT-5.5	Gap
10,000	$101	$675	$574
100,000	$1,013	$6,750	$5,738
1,000,000	$10,125	$67,500	$57,375

Where the money goes on each

GPT-5.4 mini prices output at 6x its input rate, so on this profile output is 67% of its task cost. GPT-5.5 prices output at 6x input, putting output at 67% of cost. The model with the higher output multiple rewards capping response length more; the one with the higher input share rewards prompt caching and context trimming more. Cost tells you nothing about quality: run both on twenty of your real cases before deciding, and treat the cheaper model as the default until it demonstrably fails.

Break-even against a dedicated GPU

Against a $2/hour dedicated instance ($1,460/month fixed), self-hosting overtakes GPT-5.4 mini at 144,198 tasks per month and overtakes GPT-5.5 at 21,630 tasks per month. The full method is in the self-hosting break-even guide.

Pricing the self-hosted side? Compare on-demand GPU rates:

Compare GPU cloud pricing →

Plug your own token counts into the $/task calculator, or read the full ten-model pricing comparison.

Compare against other models

Frequently asked

Which is cheaper, GPT-5.4 mini or GPT-5.5?: GPT-5.4 mini. On a task of 1,500 input and 500 output tokens across 3 calls, GPT-5.4 mini costs $0.01013 per task against $0.06750 for GPT-5.5, which makes it 6.67x cheaper (a 85% saving).
How much do GPT-5.4 mini and GPT-5.5 charge per million tokens?: GPT-5.4 mini: $0.75 per million input tokens and $4.5 per million output tokens. GPT-5.5: $5 input and $30 output. These are published list rates as of August 2026, excluding cached, batch and long-context tiers.
What does a million tasks cost on GPT-5.4 mini vs GPT-5.5?: At the same fixed profile, one million tasks cost $10,125 on GPT-5.4 mini and $67,500 on GPT-5.5. The gap comes entirely from list-price differences, not from any difference in the work done.