Gemini 3 Pro vs o3
A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.
Updated
Gemini 3 Pro specs · o3 specs- Priceo3
o3 publishes pricing ($8.00 / 1M output tokens) while Gemini 3 Pro does not.
- Context windowGemini 3 Pro
Gemini 3 Pro accepts 1.0M tokens vs 200K, 5.2× the room for long documents and codebases.
- BenchmarksGemini 3 Pro
Gemini 3 Pro leads in 1 of 2 shared benchmarks; the biggest gap is on GPQA (graduate-level reasoning), where it scores 91.9 vs 87.7.
- ModalitiesGemini 3 Pro
Gemini 3 Pro supports 4 modalities (text, vision, audio, video) vs 2 for o3.
- OpennessTie
Both are closed-weight, API-only.
On balance Gemini 3 Pro edges ahead, winning 3 of 5 categories against o3's 1. o3 publishes pricing ($8.00 / 1M output tokens) while Gemini 3 Pro does not. Gemini 3 Pro accepts 1.0M tokens vs 200K, 5.2× the room for long documents and codebases.
Gemini 3 Pro leads in 1 of 2 shared benchmarks; the biggest gap is on GPQA (graduate-level reasoning), where it scores 91.9 vs 87.7. They differ in modality coverage, Gemini 3 Pro handles text, vision, audio, video while o3 handles text, vision, which can be the deciding factor before you even look at benchmarks. Both are closed-weight, API-only.
Gemini 3 Pro is the newer of the two, released 8 months after o3, which usually means a more recent knowledge cutoff and updated safety post-training. Gemini 3 Pro is usually picked for long context and rag workloads, while o3 sees more deployments in reasoning and math. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.
Side-by-side specs
| Spec | Gemini 3 Pro | o3 |
|---|---|---|
| Provider | OpenAI | |
| Released | Dec 2025 | Apr 2025 |
| Modalities | text, vision, audio, video | text, vision |
| Context window | 1.0M tokens | 200K tokens |
| Max output | 65.5K tokens | , |
| Input · 1M | Pricing not published | $2.00 / 1M tokens |
| Output · 1M | Pricing not published | $8.00 / 1M tokens |
| Knowledge cutoff | 2025-01 | 2024-06 |
| Open weights | No | No |
| API available | Yes | Yes |
Pricing at scale
What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.
- Light usage, 100k in / 50k out per day, vs $18.00
- Heavy usage, 1M in / 500k out per day, vs $180
- RAG workload, 5M in / 200k out per day, vs $348
Light usage, 100k in / 50k out per day: pricing not directly comparable (one or both models are missing public per-token rates). Heavy usage, 1M in / 500k out per day: pricing not directly comparable (one or both models are missing public per-token rates). RAG workload, 5M in / 200k out per day: pricing not directly comparable (one or both models are missing public per-token rates).
Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.
- Gemini 3 ProPricing unavailable
- o3$0.600
Benchmarks compared
Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.
- MMLU91.8
- HumanEval95.495.0
- GPQA91.987.7
Gemini 3 Pro fits when…
- Massive 1M-token context window
- State-of-the-art vision and document understanding
- Strong reasoning at competitive price
- Long-context tasks, handles 1.0M tokens vs 200K for o3.
- Multimodal needs covering audio, video.
o3 fits when…
- Industry-leading reasoning depth at launch
- Strong on math, science, and abstract puzzles
- Tool-use during reasoning loops
Consider Gemini 3 Flash
Google's high-speed, low-cost mid-tier with the same massive context window, popular for high-volume RAG.
Frequently asked
Is Gemini 3 Pro or o3 cheaper?
Per-token pricing isn't published for at least one of these models, check each model's spec page for current rates.Which has the larger context window?
Gemini 3 Pro accepts 1.0M tokens vs 200K for o3.Is Gemini 3 Pro or o3 better for coding?
Both Gemini 3 Pro and o3 are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.Are either of these models open source?
Neither model ships open weights, both are accessible only via their respective providers' APIs.When were Gemini 3 Pro and o3 released?
Gemini 3 Pro was released by Google on 2025-12-09. o3 was released by OpenAI on 2025-04-16.
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