GPT-5.5 Pro vs GPT Realtime 2
GPT-5.5 Pro and GPT Realtime 2 are both current openai production-tier models. GPT Realtime 2 is meaningfully cheaper at $4 / $24 per 1M. GPT-5.5 Pro has a 400k context window — about 3× the 128k of GPT Realtime 2. GPT-5.5 Pro leads on coding, reasoning, general knowledge.
Specs side by side
| Metric | OpenAI GPT-5.5 Pro | OpenAI GPT Realtime 2 |
|---|---|---|
| Input price (per 1M) | $30 | $4 |
| Output price (per 1M) | $180 | $24 |
| Context window | 400k tokens | 128k tokens |
| Speed tier | slow | ultra |
| Open weights | No | No |
| EU region | No | Yes |
| Free tier | No | No |
| Prompt caching | Yes | No |
| Vision input | Yes | No |
| Extended thinking | Yes | No |
When to choose each
Choose GPT-5.5 Pro if…
- You need 400k context (3× more than GPT Realtime 2)
- HIPAA eligibility is required
- You need image input / vision
- Coding is central to your workload
- Reasoning is central to your workload
Choose GPT Realtime 2 if…
- Cost is a priority ($4 / $24 per 1M vs $30 / $180 per 1M)
- Low latency matters (ultra vs slow)
- EU data residency is required
- You need realtime speech-to-speech
Benchmark delta
GPT-5.5 Pro leads on
- Coding
- Reasoning
- General knowledge
- Long-context retrieval
- Instruction following
- Multilingual
- Tool use
GPT Realtime 2 leads on
GPT Realtime 2 has no meaningful benchmark lead in this pair.
FAQ — GPT-5.5 Pro vs GPT Realtime 2
GPT-5.5 Pro vs GPT Realtime 2 — which is better?
GPT-5.5 Pro and GPT Realtime 2 are both current openai production-tier models. GPT Realtime 2 is meaningfully cheaper at $4 / $24 per 1M. GPT-5.5 Pro has a 400k context window — about 3× the 128k of GPT Realtime 2. GPT-5.5 Pro 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 Pro pricing compare to GPT Realtime 2?
GPT-5.5 Pro costs $30 / $180 per 1M vs GPT Realtime 2 at $4 / $24 per 1M. GPT Realtime 2 is cheaper on output tokens by roughly 650%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.
Does GPT-5.5 Pro or GPT Realtime 2 have the bigger context window?
GPT-5.5 Pro has a 400k-token context window — 3× the 128k context of GPT Realtime 2. Enough for long reports and multi-document analysis.
Is there a free tier for GPT-5.5 Pro or GPT Realtime 2?
GPT-5.5 Pro: no — Paid-only — no free tier. GPT Realtime 2: no — Paid-only.
Which is better for coding — GPT-5.5 Pro or GPT Realtime 2?
GPT-5.5 Pro leads on coding benchmarks (GPT-5.5 Pro: 96/100, GPT Realtime 2: 78/100). For production coding agents also weigh tool-use performance — GPT-5.5 Pro scores 94, GPT Realtime 2 scores 84.