Claude Opus 4.5 (latest) vs GPT-5.1 Chat: API price and specs

GPT-5.1 Chat is 56% cheaper than Claude Opus 4.5 (latest) on input price.

GPT-5.1 Chat is 28% cheaper than Claude Opus 4.5 (latest) on output price.

GPT-5.1 Chat is 42% cheaper than Claude Opus 4.5 (latest) on a 1M-in / 200k-out workload.

Claude Opus 4.5 (latest) has a 56.2% larger context than GPT-5.1 Chat.

Field	Claude Opus 4.5 (latest)	GPT-5.1 Chat
Lowest input, per 1M	$2.50 +127.3%	$1.10
Median input, per 1M	$5.00 +300%	$1.25
Lowest output, per 1M	$12.50 +38.9%	$9.00
Median output, per 1M	$25.00 +150%	$10.00
Lowest unit price	—	—
Cost of 1M in + 200k out	$5.00 +72.4%	$2.90
Context	200K	128K +36%
Max output	66K	64K +2.3%
Providers	30	6 +80%
Regions	EU, GLOBAL, US	—
Accepts	application/pdf, file, image, image/gif, image/jpeg, image/png, image/webp, pdf, text	image, image/gif, image/jpeg, image/png, image/webp, pdf, text
Returns	text	image, text
Type	Text models	Text models
Free option	no	no
Cheapest provider	openrouter	poe

Your own workload: how many tokens the model gets (input) and gives back (output) - for example, in a month. The "Cost" row of the table above is recalculated for these numbers, for each model.

Computed from current offers each time the page opens; the best value of a row is bold, the percent is how far behind the best.

Providers selling both

302ai, aihubmix, helicone, orcarouter, poe, zenmux

Frequently asked questions

Which is cheaper, Claude Opus 4.5 (latest) or GPT-5.1 Chat?

GPT-5.1 Chat is 56% cheaper than Claude Opus 4.5 (latest) on input price. GPT-5.1 Chat is 28% cheaper than Claude Opus 4.5 (latest) on output price. GPT-5.1 Chat is 42% cheaper than Claude Opus 4.5 (latest) on a 1M-in / 200k-out workload.

Which has the larger context, Claude Opus 4.5 (latest) or GPT-5.1 Chat?

Claude Opus 4.5 (latest): 200K tokens; GPT-5.1 Chat: 128K tokens.

Where can I use both Claude Opus 4.5 (latest) and GPT-5.1 Chat?

302ai, aihubmix, helicone, orcarouter, poe, zenmux