GPT-5.5 vs Grok 4.3
GPT-5.5 and Grok 4.3 are both current production-tier models. Grok 4.3 is meaningfully cheaper at $1.25 / $2.5 per 1M. GPT-5.5 has a 1.1M context window — about 4× the 256k of Grok 4.3. GPT-5.5 leads on coding, long-context retrieval, instruction following.
Specs side by side
| Metric | OpenAI GPT-5.5 | xAI Grok 4.3 |
|---|---|---|
| Input price (per 1M) | $5 | $1.25 |
| Output price (per 1M) | $30 | $2.5 |
| Context window | 1.1M tokens | 256k tokens |
| Speed tier | balanced | balanced |
| Open weights | No | No |
| EU region | Yes | No |
| Free tier | No | No |
| Prompt caching | Yes | Yes |
| Vision input | Yes | Yes |
| Extended thinking | Yes | Yes |
When to choose each
Choose GPT-5.5 if…
- You need 1.1M context (4× more than Grok 4.3)
- EU data residency is required
- HIPAA eligibility is required
- You need realtime speech-to-speech
- Coding is central to your workload
- Long-context retrieval is central to your workload
Choose Grok 4.3 if…
- Cost is a priority ($1.25 / $2.5 per 1M vs $5 / $30 per 1M)
Benchmark delta
GPT-5.5 leads on
- Coding
- Long-context retrieval
- Instruction following
- Multilingual
- Vision
- Tool use
Grok 4.3 leads on
Grok 4.3 has no meaningful benchmark lead in this pair.
FAQ — GPT-5.5 vs Grok 4.3
GPT-5.5 vs Grok 4.3 — which is better?
GPT-5.5 and Grok 4.3 are both current production-tier models. Grok 4.3 is meaningfully cheaper at $1.25 / $2.5 per 1M. GPT-5.5 has a 1.1M context window — about 4× the 256k of Grok 4.3. GPT-5.5 leads on coding, long-context retrieval, instruction following. 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 Grok 4.3?
GPT-5.5 costs $5 / $30 per 1M vs Grok 4.3 at $1.25 / $2.5 per 1M. Grok 4.3 is cheaper on output tokens by roughly 1100%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.
Does GPT-5.5 or Grok 4.3 have the bigger context window?
GPT-5.5 has a 1.1M-token context window — 4× the 256k context of Grok 4.3. Enough for entire codebases, books, or multi-document RAG.
Is there a free tier for GPT-5.5 or Grok 4.3?
GPT-5.5: no — Paid-only — no free API tier; available via ChatGPT Plus/Pro. Grok 4.3: no — X Premium / SuperGrok includes Grok web chat; API is paid.
Which is better for coding — GPT-5.5 or Grok 4.3?
GPT-5.5 leads on coding benchmarks (GPT-5.5: 95/100, Grok 4.3: 91/100). For production coding agents also weigh tool-use performance — GPT-5.5 scores 94, Grok 4.3 scores 90.