Gemini 2.5 Pro vs GPT-5.4
Gemini 2.5 Pro (2025) and GPT-5.4 (2026) are frontier reasoning models from Google DeepMind and OpenAI. Gemini 2.5 Pro ships a 1M-token context window, while GPT-5.4 ships a not-yet-sourced context window. On MMLU PRO, GPT-5.4 leads by 1.3 pts. On pricing, Gemini 2.5 Pro costs $1.25/1M input tokens versus $2.5/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.
Gemini 2.5 Pro is ~100% cheaper at $1.25/1M; pay for GPT-5.4 only for coding workflow support.
Specs
| Released | 2025-06-17 | 2026-03-05 |
| Context window | 1M | — |
| Parameters | — | — |
| Architecture | decoder only | decoder only |
| License | Proprietary | Proprietary |
| Knowledge cutoff | 2025-01 | 2025-08 |
Pricing and availability
| Gemini 2.5 Pro | GPT-5.4 | |
|---|---|---|
| Input price | $1.25/1M tokens | $2.5/1M tokens |
| Output price | $10/1M tokens | $15/1M tokens |
| Providers |
Capabilities
| Gemini 2.5 Pro | GPT-5.4 | |
|---|---|---|
| Vision | ||
| Multimodal | ||
| Reasoning | ||
| Function calling | ||
| Tool use | ||
| Structured outputs | ||
| Code execution |
Benchmarks
| Benchmark | Gemini 2.5 Pro | GPT-5.4 |
|---|---|---|
| MMLU PRO | 86.2 | 87.5 |
| Google-Proof Q&A | 86.4 | 92.0 |
Deep dive
On shared benchmark coverage, MMLU PRO has Gemini 2.5 Pro at 86.2 and GPT-5.4 at 87.5, with GPT-5.4 ahead by 1.3 points; Google-Proof Q&A has Gemini 2.5 Pro at 86.4 and GPT-5.4 at 92, with GPT-5.4 ahead by 5.6 points. The largest visible gap is 5.6 points on Google-Proof Q&A, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.
The capability footprint differs most on vision: Gemini 2.5 Pro and reasoning mode: GPT-5.4. Both models share multimodal input, function calling, tool use, and structured outputs, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
For cost, Gemini 2.5 Pro lists $1.25/1M input and $10/1M output tokens, while GPT-5.4 lists $2.5/1M input and $15/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Gemini 2.5 Pro lower by about $2.38 per million blended tokens. Availability is 3 providers versus 2, so concentration risk also matters.
Choose Gemini 2.5 Pro when coding workflow support, lower input-token cost, and broader provider choice are central to the workload. Choose GPT-5.4 when coding workflow support are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which is cheaper, Gemini 2.5 Pro or GPT-5.4?
Gemini 2.5 Pro is cheaper on tracked token pricing. Gemini 2.5 Pro costs $1.25/1M input and $10/1M output tokens. GPT-5.4 costs $2.5/1M input and $15/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is Gemini 2.5 Pro or GPT-5.4 open source?
Gemini 2.5 Pro is listed under Proprietary. GPT-5.4 is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for vision, Gemini 2.5 Pro or GPT-5.4?
Gemini 2.5 Pro has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for multimodal input, Gemini 2.5 Pro or GPT-5.4?
Both Gemini 2.5 Pro and GPT-5.4 expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for reasoning mode, Gemini 2.5 Pro or GPT-5.4?
GPT-5.4 has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Where can I run Gemini 2.5 Pro and GPT-5.4?
Gemini 2.5 Pro is available on Google AI Studio, GCP Vertex AI, and OpenRouter. GPT-5.4 is available on OpenAI API and OpenRouter. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-04-24. Data sourced from public model cards and provider documentation.