Head to head
Gemini 3.1 Pro Preview vs GPT-5
Gemini 3.1 Pro Preview (Google) and GPT-5 (OpenAI) compared on intelligence, speed, context, and price — and which to choose. Both run on just4o.chat from one chat.
| Metric | Gemini 3.1 Pro Preview | GPT-5 |
|---|---|---|
| Intelligence (AA index) | 57 ✓ | 45 |
| Output speed (tokens/sec) | 132.6 ✓ | 100.1 |
| Context window | 1.0M ✓ | 400K |
| Max output | 66K | — |
| Input price / 1M | $2 | $1.25 ✓ |
| Output price / 1M | $12 | $10 ✓ |
| Released | 2026-02-19 | 2025-08-07 |
Choose Gemini 3.1 Pro Preview if you want…
- Higher intelligence (Artificial Analysis index 57)
- Faster output (~132.6 tokens/sec)
- Larger context window (1.0M)
Choose GPT-5 if you want…
- Lower price ($3.44 / 1M blended)
Gemini 3.1 Pro Preview
At the top of the Artificial Analysis Intelligence Index — ahead of every other model evaluated — Gemini 3.1 Pro Preview earns its ranking not just on raw ability but on the economics of getting there. It ran a full benchmark suite at less than half the cost of comparable frontier models, which makes it the clearest answer to the question of whether top-tier intelligence requires top-tier spend. A 38-percentage-point drop in hallucination rate over its predecessor and a 94.3% GPQA Diamond score in graduate-level scientific reasoning make it a serious tool for complex research, deep software engineering, and agentic workflows that need to get things right. Its 1-million-token context window handles entire codebases or lengthy document sets without batching. The honest caveat: time-to-first-token averages nearly 25 seconds, well above the median for comparable models, and some developers report extended waits or reliability issues under high API load. If your work is iterative and deep rather than real-time and conversational, the trade-off is usually worth it.
Full Gemini 3.1 Pro Preview details →GPT-5
GPT-5 is OpenAI's unified flagship — a single model that scales its reasoning effort up or down to match the task, rather than making you pick a separate variant. The result shows up most clearly in hard technical work: a perfect AIME 2025 score with tools, 74.9% on SWE-bench Verified, and a 1.6% error rate on medical benchmark HealthBench make it one of the more capable models available for code, math, and domain-specific research. Its 400,000-token context window handles large codebases and lengthy documents without truncation. Users consistently praise the step-up in accuracy and the meaningful reduction in hallucinations over GPT-4o. The honest caveat: GPT-5 trades warmth for precision. Early adopters widely noted that responses are shorter, cooler, and noticeably less conversational than its predecessor — a real shift if personality and back-and-forth rapport matter to your workflow. Latency is also substantial; extended reasoning produces a time-to-first-token around 68 seconds, which rules it out for anything requiring snappy replies.
Full GPT-5 details →FAQ
Which is better, Gemini 3.1 Pro Preview or GPT-5?
Gemini 3.1 Pro Preview leads on 3 of the headline metrics (higher intelligence (artificial analysis index 57); faster output (~132.6 tokens/sec); larger context window (1.0m)), while GPT-5 wins on lower price ($3.44 / 1m blended). The right pick depends on whether you prioritise capability, speed, or cost.
Is Gemini 3.1 Pro Preview or GPT-5 cheaper?
GPT-5 is cheaper at $3.44 per 1M tokens (blended), versus $4.5.
Can I use both Gemini 3.1 Pro Preview and GPT-5?
Yes. Both are available on just4o.chat from a single chat — you can switch between them per message with no separate subscriptions.