o3 vs GPT-5.4.

Which is cheaper: o3 or GPT-5.4?

On a standard 1,500-input / 500-output call, o3 is about 38% cheaper — $0.0070 versus $0.0112 per call. At 10,000 calls a month that is roughly $70.00 vs $112.50.

Output tokens cost several times more than input on both models, so the more your workload leans toward long generated answers, the more the output rate dominates the bill.

Side-by-side specifications

Metric	o3	GPT-5.4
Vendor	OpenAI	OpenAI
Input price / M tokens	$2.00	$2.50
Output price / M tokens	$8.00	$15.00
Context window	200K	1M
Cost per typical call	$0.0070	$0.0112
Cost per 10,000 calls	$70.00	$112.50

When to pick which

• o3 is cheaper on both input ($2.00 vs $2.50) and output ($8.00 vs $15.00) per million — so it wins on price for any workload mix.
• GPT-5.4 only makes sense if your evals, tokenizer efficiency on non-English text, or context needs favour it.

Beyond the per-token math, tokenizer efficiency on non-English text and your own quality evals can shift the real cost. On context, GPT-5.4 offers the larger window (1M), which matters for long documents and agent histories. Price your actual prompt in the language you serve with the calculator before committing.

Prompt caching and batching

Both providers support prompt caching (cached input bills at roughly 10% of the standard rate) and batch processing (about 50% off for 24-hour-tolerant jobs). If one model lets you cache a larger static prefix in your setup, it can become cheaper in practice even when its headline rate is higher.

The bottom line

o3 wins on raw price for a typical workload. Pick GPT-5.4 only when its quality, context, or tokenizer advantages on your specific task outweigh the difference.

FAQ

Is o3 or GPT-5.4 cheaper?

o3 — about 38% cheaper on a typical 1,500-input / 500-output call ($0.0070 vs $0.0112).

What does each cost per million tokens?

o3: $2.00 input / $8.00 output. GPT-5.4: $2.50 input / $15.00 output.

Which should I choose for output-heavy generation?

The one with the lower output rate, since generation is output-bound: o3 ($8.00/M output).