Gemini 3 Flash vs GPT Realtime 2

Gemini 3 Flash and GPT Realtime 2 are both current production-tier models. Gemini 3 Flash is meaningfully cheaper at $0.50 / $3 per 1M. Gemini 3 Flash has a 1M context window — about 8× the 128k of GPT Realtime 2. Gemini 3 Flash leads on coding, reasoning, long-context retrieval.

Specs side by side

Metric
Google
Gemini 3 Flash
OpenAI
GPT Realtime 2
Input price (per 1M)$0.5$4
Output price (per 1M)$3$24
Context window1M tokens128k tokens
Speed tierfastultra
Open weightsNoNo
EU regionYesYes
Free tierGoogle AI StudioNo
Prompt cachingYesNo
Vision inputYesNo
Extended thinkingYesNo

When to choose each

Google Free tier

Choose Gemini 3 Flash if…

  • Cost is a priority ($0.50 / $3 per 1M vs $4 / $24 per 1M)
  • You need 1M context (8× more than GPT Realtime 2)
  • HIPAA eligibility is required
  • You need image input / vision
  • You want a free tier for prototyping
  • Coding is central to your workload
  • Reasoning is central to your workload
OpenAI

Choose GPT Realtime 2 if…

  • You need realtime speech-to-speech

Benchmark delta

Gemini 3 Flash leads on

  • Coding
  • Reasoning
  • Long-context retrieval
  • Multilingual

GPT Realtime 2 leads on

GPT Realtime 2 has no meaningful benchmark lead in this pair.

FAQ — Gemini 3 Flash vs GPT Realtime 2

Gemini 3 Flash vs GPT Realtime 2 — which is better?

Gemini 3 Flash and GPT Realtime 2 are both current production-tier models. Gemini 3 Flash is meaningfully cheaper at $0.50 / $3 per 1M. Gemini 3 Flash has a 1M context window — about 8× the 128k of GPT Realtime 2. Gemini 3 Flash leads on coding, reasoning, long-context retrieval. The right pick depends on your use case — see "When to choose each" above for a data-driven decision.

How does Gemini 3 Flash pricing compare to GPT Realtime 2?

Gemini 3 Flash costs $0.50 / $3 per 1M vs GPT Realtime 2 at $4 / $24 per 1M. Gemini 3 Flash is cheaper on output tokens by roughly 700%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.

Does Gemini 3 Flash or GPT Realtime 2 have the bigger context window?

Gemini 3 Flash has a 1M-token context window — 8× the 128k context of GPT Realtime 2. Enough for entire codebases, books, or multi-document RAG.

Is there a free tier for Gemini 3 Flash or GPT Realtime 2?

Gemini 3 Flash: yes — Reduced daily quota; rate-limited for prototyping. GPT Realtime 2: no — Paid-only.

Which is better for coding — Gemini 3 Flash or GPT Realtime 2?

Gemini 3 Flash leads on coding benchmarks (Gemini 3 Flash: 84/100, GPT Realtime 2: 78/100). For production coding agents also weigh tool-use performance — Gemini 3 Flash scores 85, GPT Realtime 2 scores 84.