o1 vs o3 vs Claude Opus 4
o3 comes out ahead, 58 to 49 and 48 on our weighted score, and it is the cheaper option too.
OpenAIo1
49/100- ECI141.9
- Price$15.00 / $60.00
- Context200K
- Our pickOpenAI
o3
58/100- ECI146.9
- Price$2.00 / $8.00
- Context200K
AnthropicClaude Opus 4
48/100- ECI142.7
- Price$15.00 / $75.00
- Context200K
o3 is our pick
o3 is the better all-round choice, scoring 58/100 against o1 (49) and Claude Opus 4 (48). It leads on capability and price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
- Capabilityo3Capabilities Index (ECI): o3 146.9 · Claude Opus 4 142.7 · o1 141.9
- Lowest priceo3o3 $3.50 · o1 $26.25 · Claude Opus 4 $30.00 per 1M tokens (3:1 blend)
- Longest contextAbout the sameo1 200,000 · o3 200,000 · Claude Opus 4 200,000 tokens
- Widest inputsSame inputso1: Text, Images, PDFs · o3: Text, Images, PDFs · Claude Opus 4: Text, Images, PDFs
- Self-hostingNo open weightsAll three are available only through APIs
| Measure | Weight | o1 | o3 | Claude Opus 4 |
|---|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 50% | 68 | 74 | 69 |
| Price | 25% | 0 | 24 | 0 |
| Inputs & features | 15% | 80 | 80 | 70 |
| Context window | 10% | 32 | 32 | 32 |
| Overall | 100% | 49/100 | 58/100 | 48/100 |
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | o1OpenAI | o3OpenAI | Claude Opus 4Anthropic |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | 141.9 | 146.9 (best) | 142.7 |
| ECI rank | #92 of 148 | #63 of 148 (best) | #87 of 148 |
| GPQA DiamondGraduate-level science questions | 76.8% | 81.8% (best) | 76.3% |
| FrontierMath Tiers 1–3Research-level mathematics | 14.7% | 33.3% (best) | — |
| OTIS Mock AIME 2024–2025Competition mathematics | 73.3% | 84.4% (best) | 64.4% |
| SWE-bench VerifiedFixing real GitHub issues | — | 62.3% | 70.7% (best) |
| SimpleQA VerifiedShort factual questions | 41.1% | 49.4% (best) | — |
| Price per million tokens | |||
| Input | $15.00 | $2.00 (best) | $15.00 |
| Output | $60.00 | $8.00 (best) | $75.00 |
| Cached input | $7.50 | $0.50 (best) | — |
| Blended (3:1) | $26.25 | $3.50 (best) | $30.00 |
| Long-context rate | Same rate | Same rate | Same rate |
| Price source | Official OpenAI API | Official OpenAI API | Median of 5 providers |
| Limits | |||
| Context window | 200,000 tokens | 200,000 tokens | 200,000 tokens |
| Max output | 100,000 tokens (best) | 100,000 tokens (best) | 32,000 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | Yes | Yes |
| PDFs | Yes | Yes | Yes |
| Audio | No | No | No |
| Video | No | No | No |
| Reasoning | Yeslow · medium · high | Yeslow · medium · high | Yes |
| Tool calling | Yes | Yes | Yes |
| Structured output | Yes | Yes | No |
| Availability | |||
| Weights | Proprietary | Proprietary | Proprietary |
| API model ID | o1 | o3 | — |
| API providers | 9 | 18 (best) | 5 |
| Released | Dec 5, 2024 | Apr 16, 2025 | May 22, 2025 |
| Knowledge cutoff | Sep 2023 | May 2024 | Mar 31, 2025 |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- o1$270.00
- o3$36.00
- Claude Opus 4$300.00
Which should you choose?
Which is better: o1, o3 or Claude Opus 4?
o3 is the better all-round choice, scoring 58/100 against o1 (49) and Claude Opus 4 (48). It leads on capability and price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
Which is cheaper, o1, o3 or Claude Opus 4?
o3 is cheaper at $2.00 input / $8.00 output per million tokens (official OpenAI API price). o1 costs $15.00 input / $60.00 output per million tokens (official OpenAI API price); Claude Opus 4 costs $15.00 input / $75.00 output per million tokens (median across 5 API providers). At a typical mix of three input tokens to one output token, that is $3.50 per million tokens for o3 versus $26.25 for o1 (7.5× as much) and $30.00 for Claude Opus 4 (8.6× as much).
Which scores higher on benchmarks?
o3 scores higher on the Capabilities Index (ECI): o3 146.9 (#63 of 148), Claude Opus 4 142.7 (#87 of 148) and o1 141.9 (#92 of 148). Their confidence ranges do not overlap (144.9–148.6 vs 140.2–144.2), so the gap is a real one. On individual benchmarks: GPQA Diamond — o3 81.8%, o1 76.8%, Claude Opus 4 76.3%; OTIS Mock AIME 2024–2025 — o3 84.4%, o1 73.3%, Claude Opus 4 64.4%.
Which is better for coding?
There are no published SWE-bench Verified results for o1 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. All three support tool calling for agent workflows.
Which has the bigger context window?
o1, o3 and Claude Opus 4 share the same 200,000-token context window. Maximum output per response: o1 up to 100,000, o3 up to 100,000, Claude Opus 4 up to 32,000 tokens.
Which can read images, PDFs, audio or video?
o1 accepts text, images and PDFs; o3 accepts text, images and PDFs; Claude Opus 4 accepts text, images and PDFs. They handle the same number of input types.
Are any of these open source?
No. o1, o3 and Claude Opus 4 are proprietary and only available through APIs and apps.
Which is newer?
Claude Opus 4 is the newest, released May 22, 2025. o3 came out Apr 16, 2025; o1 came out Dec 5, 2024. Knowledge cutoff: o1 Sep 2023, o3 May 2024, Claude Opus 4 Mar 31, 2025.
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.
