GLM-5.2 vs GPT Realtime 2
GLM-5.2 and GPT Realtime 2 are both current production-tier models. GLM-5.2 is meaningfully cheaper at $1.4 / $4.4 per 1M. GLM-5.2 has a 1M context window — about 8× the 128k of GPT Realtime 2. GLM-5.2 leads on coding, reasoning, long-context retrieval.
Specs side by side
| Metric | Z.ai GLM-5.2 | OpenAI GPT Realtime 2 |
|---|---|---|
| Input price (per 1M) | $1.4 | $4 |
| Output price (per 1M) | $4.4 | $24 |
| Context window | 1M tokens | 128k tokens |
| Speed tier | balanced | ultra |
| Open weights | Yes | No |
| EU region | No | Yes |
| Free tier | bigmodel.cn | No |
| Prompt caching | Yes | No |
| Vision input | No | No |
| Extended thinking | Yes | No |
When to choose each
Choose GLM-5.2 if…
- Cost is a priority ($1.4 / $4.4 per 1M vs $4 / $24 per 1M)
- You need 1M context (8× more than GPT Realtime 2)
- You need open weights for self-hosting or fine-tuning
- You want a free tier for prototyping
- Coding is central to your workload
- Reasoning is central to your workload
Choose GPT Realtime 2 if…
- Low latency matters (ultra vs balanced)
- EU data residency is required
- You need realtime speech-to-speech
Benchmark delta
GLM-5.2 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 — GLM-5.2 vs GPT Realtime 2
GLM-5.2 vs GPT Realtime 2 — which is better?
GLM-5.2 and GPT Realtime 2 are both current production-tier models. GLM-5.2 is meaningfully cheaper at $1.4 / $4.4 per 1M. GLM-5.2 has a 1M context window — about 8× the 128k of GPT Realtime 2. GLM-5.2 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 GLM-5.2 pricing compare to GPT Realtime 2?
GLM-5.2 costs $1.4 / $4.4 per 1M vs GPT Realtime 2 at $4 / $24 per 1M. GLM-5.2 is cheaper on output tokens by roughly 445%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.
Does GLM-5.2 or GPT Realtime 2 have the bigger context window?
GLM-5.2 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 GLM-5.2 or GPT Realtime 2?
GLM-5.2: yes — Free tier with monthly token allowance. GPT Realtime 2: no — Paid-only.
Which is better for coding — GLM-5.2 or GPT Realtime 2?
GLM-5.2 leads on coding benchmarks (GLM-5.2: 93/100, GPT Realtime 2: 78/100). For production coding agents also weigh tool-use performance — GLM-5.2 scores 86, GPT Realtime 2 scores 84.