GPT-5.5 vs GPT Realtime

GPT-5.5 and GPT Realtime are both current openai production-tier models. GPT Realtime is meaningfully cheaper at $4 / $16 per 1M. GPT-5.5 has a 1.1M context window — about 8× the 128k of GPT Realtime. GPT-5.5 leads on coding, reasoning, general knowledge.

Specs side by side

Metric
OpenAI
GPT-5.5
OpenAI
GPT Realtime
Input price (per 1M)$5$4
Output price (per 1M)$30$16
Context window1.1M tokens128k tokens
Speed tierbalancedultra
Open weightsNoNo
EU regionYesYes
Free tierNoNo
Prompt cachingYesNo
Vision inputYesNo
Extended thinkingYesNo

When to choose each

OpenAI

Choose GPT-5.5 if…

  • You need 1.1M context (8× more than GPT Realtime)
  • HIPAA eligibility is required
  • You need image input / vision
  • Coding is central to your workload
  • Reasoning is central to your workload
OpenAI

Choose GPT Realtime if…

  • Cost is a priority ($4 / $16 per 1M vs $5 / $30 per 1M)
  • Low latency matters (ultra vs balanced)

Benchmark delta

GPT-5.5 leads on

  • Coding
  • Reasoning
  • General knowledge
  • Long-context retrieval
  • Instruction following
  • Multilingual
  • Tool use

GPT Realtime leads on

GPT Realtime has no meaningful benchmark lead in this pair.

FAQ — GPT-5.5 vs GPT Realtime

GPT-5.5 vs GPT Realtime — which is better?

GPT-5.5 and GPT Realtime are both current openai production-tier models. GPT Realtime is meaningfully cheaper at $4 / $16 per 1M. GPT-5.5 has a 1.1M context window — about 8× the 128k of GPT Realtime. GPT-5.5 leads on coding, reasoning, general knowledge. The right pick depends on your use case — see "When to choose each" above for a data-driven decision.

How does GPT-5.5 pricing compare to GPT Realtime?

GPT-5.5 costs $5 / $30 per 1M vs GPT Realtime at $4 / $16 per 1M. GPT Realtime is cheaper on output tokens by roughly 88%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.

Does GPT-5.5 or GPT Realtime have the bigger context window?

GPT-5.5 has a 1.1M-token context window — 8× the 128k context of GPT Realtime. Enough for entire codebases, books, or multi-document RAG.

Is there a free tier for GPT-5.5 or GPT Realtime?

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

Which is better for coding — GPT-5.5 or GPT Realtime?

GPT-5.5 leads on coding benchmarks (GPT-5.5: 95/100, GPT Realtime: 78/100). For production coding agents also weigh tool-use performance — GPT-5.5 scores 94, GPT Realtime scores 84.