GPT-5.4 Pro vs GPT-5.5

GPT-5.4 Pro and GPT-5.5 are both current openai production-tier models. GPT-5.5 is meaningfully cheaper at $5 / $30 per 1M. GPT-5.5 has a 1.1M context window — about 3× the 400k of GPT-5.4 Pro.

Specs side by side

Metric
OpenAI
GPT-5.4 Pro
OpenAI
GPT-5.5
Input price (per 1M)$30$5
Output price (per 1M)$180$30
Context window400k tokens1.1M tokens
Speed tierslowbalanced
Open weightsNoNo
EU regionNoYes
Free tierNoNo
Prompt cachingYesYes
Vision inputYesYes
Extended thinkingYesYes

When to choose each

OpenAI

Choose GPT-5.4 Pro if…

  • GPT-5.4 Pro is in the same tier as GPT-5.5 — pick by provider preference or API ecosystem
OpenAI

Choose GPT-5.5 if…

  • Cost is a priority ($5 / $30 per 1M vs $30 / $180 per 1M)
  • You need 1.1M context (3× more than GPT-5.4 Pro)
  • EU data residency is required
  • You need realtime speech-to-speech

Benchmark delta

GPT-5.4 Pro leads on

GPT-5.4 Pro has no meaningful benchmark lead in this pair.

GPT-5.5 leads on

GPT-5.5 has no meaningful benchmark lead in this pair.

FAQ — GPT-5.4 Pro vs GPT-5.5

GPT-5.4 Pro vs GPT-5.5 — which is better?

GPT-5.4 Pro and GPT-5.5 are both current openai production-tier models. GPT-5.5 is meaningfully cheaper at $5 / $30 per 1M. GPT-5.5 has a 1.1M context window — about 3× the 400k of GPT-5.4 Pro. The right pick depends on your use case — see "When to choose each" above for a data-driven decision.

How does GPT-5.4 Pro pricing compare to GPT-5.5?

GPT-5.4 Pro costs $30 / $180 per 1M vs GPT-5.5 at $5 / $30 per 1M. GPT-5.5 is cheaper on output tokens by roughly 500%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.

Does GPT-5.4 Pro or GPT-5.5 have the bigger context window?

GPT-5.5 has a 1.1M-token context window — 3× the 400k context of GPT-5.4 Pro. Enough for entire codebases, books, or multi-document RAG.

Is there a free tier for GPT-5.4 Pro or GPT-5.5?

GPT-5.4 Pro: no — Paid-only — no free tier. GPT-5.5: no — Paid-only — no free API tier; available via ChatGPT Plus/Pro.

Which is better for coding — GPT-5.4 Pro or GPT-5.5?

GPT-5.4 Pro leads on coding benchmarks (GPT-5.4 Pro: 96/100, GPT-5.5: 95/100). For production coding agents also weigh tool-use performance — GPT-5.4 Pro scores 94, GPT-5.5 scores 94.