o3 vs Gemini 2.0 Flash
o3 comes out ahead, 70 to 65 on our weighted score, and it is the cheaper option too.
- Our pick
OpenAIo3
70/100- ECI146.9
- Price$2.00 / $8.00
- Context200K
GoogleGemini 2.0 Flash
65/100- ECI134.7
- Price—
- Context1.05M
Add a model
Make it a three-way comparison.
o3 is our pick
o3 is the better all-round choice, scoring 70/100 against Gemini 2.0 Flash (65). It leads on capability. Gemini 2.0 Flash wins on inputs & features and context window. The score weighs capability 67%, inputs & features 20%, context window 13%.
- Capabilityo3Capabilities Index (ECI): o3 146.9 · Gemini 2.0 Flash 134.7
- Lowest priceo3o3 $3.50 per 1M tokens (3:1 blend) · Gemini 2.0 Flash unpriced
- Longest contextGemini 2.0 FlashGemini 2.0 Flash 1,048,576 · o3 200,000 tokens
- Widest inputsGemini 2.0 Flasho3: Text, Images, PDFs · Gemini 2.0 Flash: Text, Images, PDFs, Audio, Video
- Self-hostingNo open weightsBoth are available only through APIs
| Measure | Weight | o3 | Gemini 2.0 Flash |
|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 67% | 74 | 59 |
| Inputs & features | 20% | 80 | 90 |
| Context window | 13% | 32 | 61 |
| Overall | 100% | 70/100 | 65/100 |
Left out because at least one model lacks the data: price. The remaining weights were rescaled.
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | o3OpenAI | Gemini 2.0 FlashGoogle |
|---|---|---|
| Capability | ||
| Capabilities Index (ECI) | 146.9 (best) | 134.7 |
| ECI rank | #63 of 148 (best) | #116 of 148 |
| GPQA DiamondGraduate-level science questions | 81.8% | — |
| FrontierMath Tiers 1–3Research-level mathematics | 33.3% | — |
| OTIS Mock AIME 2024–2025Competition mathematics | 84.4% | — |
| SWE-bench VerifiedFixing real GitHub issues | 62.3% | — |
| SimpleQA VerifiedShort factual questions | 49.4% | — |
| Price per million tokens | ||
| Input | $2.00 | — |
| Output | $8.00 | — |
| Cached input | $0.50 | — |
| Blended (3:1) | $3.50 | — |
| Long-context rate | Same rate | — |
| Price source | Official OpenAI API | — |
| Limits | ||
| Context window | 200,000 tokens | 1,048,576 tokens (best) |
| Max output | 100,000 tokens (best) | 8,192 tokens |
| Inputs and features | ||
| Text | Yes | Yes |
| Images | Yes | Yes |
| PDFs | Yes | Yes |
| Audio | No | Yes |
| Video | No | Yes |
| Reasoning | Yeslow · medium · high | No |
| Tool calling | Yes | Yes |
| Structured output | Yes | Yes |
| Availability | ||
| Weights | Proprietary | Proprietary |
| API model ID | o3 | — |
| API providers | 18 | — |
| Released | Apr 16, 2025 | Dec 11, 2024 |
| Knowledge cutoff | May 2024 | Jun 2024 |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- o3$36.00
- Gemini 2.0 Flash—
Which should you choose?
Which is better: o3 or Gemini 2.0 Flash?
o3 is the better all-round choice, scoring 70/100 against Gemini 2.0 Flash (65). It leads on capability. Gemini 2.0 Flash wins on inputs & features and context window. The score weighs capability 67%, inputs & features 20%, context window 13%.
Which is cheaper, o3 or Gemini 2.0 Flash?
o3 is cheaper at $2.00 input / $8.00 output per million tokens (official OpenAI API price). . At a typical mix of three input tokens to one output token, that is $3.50 per million tokens for o3 versus . Gemini 2.0 Flash has no published per-token price.
Which scores higher on benchmarks?
o3 scores higher on the Capabilities Index (ECI): o3 146.9 (#63 of 148) and Gemini 2.0 Flash 134.7 (#116 of 148). Their confidence ranges do not overlap (144.9–148.6 vs 124.3–136.7), so the gap is a real one.
Which is better for coding?
There are no published SWE-bench Verified results for Gemini 2.0 Flash yet, so there is no like-for-like coding score. On overall capability, o3 leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.
Which has the bigger context window?
Gemini 2.0 Flash has the largest context window at 1,048,576 tokens, against 200,000 for o3. Maximum output per response: o3 up to 100,000, Gemini 2.0 Flash up to 8,192 tokens.
Which can read images, PDFs, audio or video?
o3 accepts text, images and PDFs; Gemini 2.0 Flash accepts text, images, PDFs, audio and video. Gemini 2.0 Flash handles the widest range of inputs.
Are any of these open source?
No. o3 and Gemini 2.0 Flash are proprietary and only available through APIs and apps.
Which is newer?
o3 is the newest, released Apr 16, 2025. Gemini 2.0 Flash came out Dec 11, 2024. Knowledge cutoff: o3 May 2024, Gemini 2.0 Flash Jun 2024.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.
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