Head to head

GPT-5 vs GPT-5.4

GPT-5 (OpenAI) and GPT-5.4 (OpenAI) compared on intelligence, speed, context, and price — and which to choose. Both run on just4o.chat from one chat.

MetricGPT-5GPT-5.4
Intelligence (AA index)4557
Output speed (tokens/sec)100.1163.4
Context window400K1.1M
Max output
Input price / 1M$1.25$2.5
Output price / 1M$10$15
Released2025-08-072026-03

Choose GPT-5 if you want…

  • Lower price ($3.44 / 1M blended)

Choose GPT-5.4 if you want…

  • Higher intelligence (Artificial Analysis index 57)
  • Faster output (~163.4 tokens/sec)
  • Larger context window (1.1M)

GPT-5

GPT-5 is OpenAI's unified flagship — a single model that scales its reasoning effort up or down to match the task, rather than making you pick a separate variant. The result shows up most clearly in hard technical work: a perfect AIME 2025 score with tools, 74.9% on SWE-bench Verified, and a 1.6% error rate on medical benchmark HealthBench make it one of the more capable models available for code, math, and domain-specific research. Its 400,000-token context window handles large codebases and lengthy documents without truncation. Users consistently praise the step-up in accuracy and the meaningful reduction in hallucinations over GPT-4o. The honest caveat: GPT-5 trades warmth for precision. Early adopters widely noted that responses are shorter, cooler, and noticeably less conversational than its predecessor — a real shift if personality and back-and-forth rapport matter to your workflow. Latency is also substantial; extended reasoning produces a time-to-first-token around 68 seconds, which rules it out for anything requiring snappy replies.

Full GPT-5 details →

GPT-5.4

GPT-5.4 was built for the actual work that happens inside offices — financial modeling, legal analysis, complex codebases, and multi-step document workflows — rather than for chasing narrow benchmarks. That strategic shift shows in the numbers: it matched or outperformed human professionals in 83% of head-to-head comparisons, and developers have called its coding output "flawless," with some declaring it the definitive choice for complex software engineering work. Native computer-use capabilities let it operate browsers and desktop apps directly, and it scored above the human baseline on UI interaction tasks. The 1.05 million token context window handles large codebases and lengthy legal documents in a single pass, though you need to configure it explicitly — the default is 272K. Where GPT-5.4 falls short is nuance: it tends to interpret requests too literally, missing the intent behind ambiguous prompts in ways that Claude handles more naturally. Writing personality is another common frustration, with verbose follow-up suggestions that can feel mechanical. For structured professional tasks where thoroughness and tool integration matter more than prose feel, it is the strongest model in the GPT-5 line prior to the release of GPT-5.5.

Full GPT-5.4 details →

FAQ

Which is better, GPT-5 or GPT-5.4?

GPT-5.4 leads on 3 of the headline metrics (higher intelligence (artificial analysis index 57); faster output (~163.4 tokens/sec); larger context window (1.1m)), while GPT-5 wins on lower price ($3.44 / 1m blended). The right pick depends on your priorities.

Is GPT-5 or GPT-5.4 cheaper?

GPT-5 is cheaper at $3.44 per 1M tokens (blended), versus $5.63.

Can I use both GPT-5 and GPT-5.4?

Yes. Both are available on just4o.chat from a single chat — you can switch between them per message with no separate subscriptions.