Is GPT-5.4 better than o3?

On accuracy they are statistically tied: GPT-5.4 scored 72.5% and o3 72.5% on the same 80 questions from open datasets. Similar accuracy; o3 costs less per question.

Which is cheaper, GPT-5.4 or o3?

o3 is cheaper: $0.0088 per question as billed, against $0.011. List prices: GPT-5.4 $2.5 in / $15 out, o3 $2 in / $8 out per million tokens.

Which is faster, GPT-5.4 or o3?

o3 is faster at 163 output tokens per second, against 55. Time to first token: 1.7 s for GPT-5.4, 1.2 s for o3.

Which has the larger context window, GPT-5.4 or o3?

GPT-5.4, with 1.1M tokens against 200k.

Head to head · tested 27 Oct 2026

GPT-5.4 vs o3: accuracy, speed and price

Similar accuracy; o3 costs less per question.

OpenAIGPT-5.472.5% score · #21$0.011 per question55 tok/s

OpenAIo372.5% score · #21$0.0088 per question163 tok/s

Verdict

Built from the measurements below

Accuracy is too close to call: GPT-5.4 scored 72.5% and o3 72.5% on the same 80 questions, a gap within what chance alone could produce.
o3 is 1.3× cheaper per question as billed ($0.0088 vs $0.011), reasoning tokens included.
o3 generates text 3.0× faster: 163 tokens per second against 55.
o3 starts answering sooner: 1.2 s to the first token, against 1.7 s for GPT-5.4.
GPT-5.4 accepts more context: 1.1M tokens against 200k.

Which should you choose?

Choose GPT-5.4 for a 1.1M-token context window and more hosts to choose from on OpenRouter (3 against 1). Choose o3 for the lower cost per correct answer ($0.012 against $0.016), faster streaming and a quicker first token. The widest subject gap is in medicine: o3 answered 7 of 11 correctly, GPT-5.4 4 of 11. With so few questions per subject, treat this as a lead to test on your own prompts, not a result.

Accuracy gap +0.0 points (z = 0.00). A winner is called only when z is at least 1.96, the usual 95% threshold. Speed, latency and price need a 10% margin.

Head to head

Same questions, same prompt, same API

Measure	GPT-5.4	o3	Edge
Verification scoreHigher is better	72.5%	72.5%	Too close to call
Cost per questionLower is better	$0.011	$0.0088	o3
Output speedHigher is better	55	163	o3
Time to first tokenLower is better	1.7 s	1.2 s	o3
End-to-end response timeLower is better	8.7 s	3.9 s	o3
Tokens per questionLower is better	706	1,025	GPT-5.4
Context windowHigher is better	1.1M	200k	GPT-5.4

Side by side

Bars are scaled to the larger of the two values. The winner on each measure is marked in bold.

Every measure

GPT-5.4 first, o3 second

Verification scorehigher is better

GPT-5.472.5%

o372.5%

Cost per questionlower is better

GPT-5.4$0.011

o3$0.0088

Output speedhigher is better

GPT-5.455

o3163

Time to first tokenlower is better

GPT-5.41.7 s

o31.2 s

End-to-end response timelower is better

GPT-5.48.7 s

o33.9 s

Tokens per questionlower is better

GPT-5.4706

o31,025

Context windowhigher is better

GPT-5.41.1M

o3200k

Score vs. cost per question

Both models in color, every other model in grey

Results by subject and dataset

Questions answered correctly. Small samples: a gap of one or two questions is noise.

Subject	Questions	GPT-5.4	o3
Science	30	25/30	23/30
Engineering	15	10/15	8/15
Medicine	11	4/11	7/11
Economics	9	8/9	7/9
Law	6	4/6	5/6
Humanities & social science	9	7/9	8/9
SuperGPQA dataset	50	32/50	30/50
MMLU-Pro dataset	30	26/30	28/30

Specifications and pricing

From OpenRouter's catalogue, plus the leaderboard's test dates

Specification	GPT-5.4	o3
Creator	OpenAI	OpenAI
Released	5 Mar 2026	16 Apr 2025
Weights	—	—
Reasoning	Yes	Yes
Input	text, image, file	image, text, file
Output	text	text
Context window	1.1M tokens	200k tokens
Knowledge cutoff	—	30 Jun 2024
List price in / out per 1M	$2.5 / $15	$2 / $8
Blended price per 1M (3:1)	$5.63	$3.50
Cheapest host	OpenAI · $1.25 / $7.5	OpenAI · $2 / $8
Hosts on OpenRouter	3	1
Last tested	25 Oct 2026	27 Oct 2026

Compare any two models →

GPT-5.4 vs o3: frequently asked questions

Is GPT-5.4 better than o3?: On accuracy they are statistically tied: GPT-5.4 scored 72.5% and o3 72.5% on the same 80 questions from open datasets. Similar accuracy; o3 costs less per question.
Which is cheaper, GPT-5.4 or o3?: o3 is cheaper: $0.0088 per question as billed, against $0.011. List prices: GPT-5.4 $2.5 in / $15 out, o3 $2 in / $8 out per million tokens.
Which is faster, GPT-5.4 or o3?: o3 is faster at 163 output tokens per second, against 55. Time to first token: 1.7 s for GPT-5.4, 1.2 s for o3.
Which has the larger context window, GPT-5.4 or o3?: GPT-5.4, with 1.1M tokens against 200k.