GPT-5 Pro vs Claude Opus 5 vs Claude Opus 4.5
Claude Opus 5 comes out ahead, 66 to 55 and 54 on our weighted score.
OpenAIGPT-5 Pro
54/100- ECI150.3
- Price$15.00 / $120.00
- Context400K
- Our pick
AnthropicClaude Opus 5
66/100- ECI162.9
- Price$5.00 / $25.00
- Context1M
- Anthropic
Claude Opus 4.5
55/100- ECI150.1
- Price$5.00 / $25.00
- Context200K
Claude Opus 5 is our pick
Claude Opus 5 is the better all-round choice, scoring 66/100 against Claude Opus 4.5 (55) and GPT-5 Pro (54). It leads on capability and context window. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
- CapabilityClaude Opus 5Capabilities Index (ECI): Claude Opus 5 162.9 · GPT-5 Pro 150.3 · Claude Opus 4.5 150.1
- Lowest priceClaude Opus 5 and Claude Opus 4.5Claude Opus 5 $10.00 · Claude Opus 4.5 $10.00 · GPT-5 Pro $41.25 per 1M tokens (3:1 blend)
- Longest contextClaude Opus 5Claude Opus 5 1,000,000 · GPT-5 Pro 400,000 · Claude Opus 4.5 200,000 tokens
- Widest inputsClaude Opus 5 and Claude Opus 4.5GPT-5 Pro: Text, Images · Claude Opus 5: Text, Images, PDFs · Claude Opus 4.5: Text, Images, PDFs
- Self-hostingNo open weightsAll three are available only through APIs
| Measure | Weight | GPT-5 Pro | Claude Opus 5 | Claude Opus 4.5 |
|---|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 50% | 78 | 94 | 78 |
| Price | 25% | 0 | 2 | 2 |
| Inputs & features | 15% | 70 | 80 | 80 |
| Context window | 10% | 44 | 60 | 32 |
| Overall | 100% | 54/100 | 66/100 | 55/100 |
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | GPT-5 ProOpenAI | Claude Opus 5Anthropic | Claude Opus 4.5Anthropic |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | 150.3 | 162.9 (best) | 150.1 |
| ECI rank | #46 of 148 | #5 of 148 (best) | #48 of 148 |
| GPQA DiamondGraduate-level science questions | — | 93.9% (best) | 86.1% |
| FrontierMath Tiers 1–3Research-level mathematics | 55.8% | 85.6% (best) | 34.4% |
| OTIS Mock AIME 2024–2025Competition mathematics | — | 98.9% (best) | 86.1% |
| SWE-bench VerifiedFixing real GitHub issues | — | — | 76.7% |
| SimpleQA VerifiedShort factual questions | — | 59.9% (best) | 45.7% |
| Price per million tokens | |||
| Input | $15.00 | $5.00 (best) | $5.00 (best) |
| Output | $120.00 | $25.00 (best) | $25.00 (best) |
| Cached input | — | $0.50 | $0.50 |
| Blended (3:1) | $41.25 | $10.00 (best) | $10.00 (best) |
| Long-context rate | Same rate | Same rate | Same rate |
| Price source | Official OpenAI API | Official Anthropic API | Official Anthropic API |
| Limits | |||
| Context window | 400,000 tokens | 1,000,000 tokens (best) | 200,000 tokens |
| Max output | 272,000 tokens (best) | 128,000 tokens | 64,000 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | Yes | Yes |
| PDFs | No | Yes | Yes |
| Audio | No | No | No |
| Video | No | No | No |
| Reasoning | Yeshigh | Yeslow · medium · high · xhigh · max | Yeslow · medium · high |
| Tool calling | Yes | Yes | Yes |
| Structured output | Yes | Yes | Yes |
| Availability | |||
| Weights | Proprietary | Proprietary | Proprietary |
| API model ID | gpt-5-pro | claude-opus-5 | claude-opus-4-5 |
| API providers | 12 | 35 (best) | 28 |
| Released | Oct 6, 2025 | Jul 24, 2026 | Nov 24, 2025 |
| Knowledge cutoff | Sep 30, 2024 | May 2026 | May 2025 |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- GPT-5 Pro$390.00
- Claude Opus 5$100.00
- Claude Opus 4.5$100.00
Which should you choose?
Which is better: GPT-5 Pro, Claude Opus 5 or Claude Opus 4.5?
Claude Opus 5 is the better all-round choice, scoring 66/100 against Claude Opus 4.5 (55) and GPT-5 Pro (54). It leads on capability and context window. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
Which is cheaper, GPT-5 Pro, Claude Opus 5 or Claude Opus 4.5?
Claude Opus 5 is cheaper at $5.00 input / $25.00 output per million tokens (official Anthropic API price). Claude Opus 4.5 costs $5.00 input / $25.00 output per million tokens (official Anthropic API price); GPT-5 Pro costs $15.00 input / $120.00 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $10.00 per million tokens for Claude Opus 5 versus $10.00 for Claude Opus 4.5 (1× as much) and $41.25 for GPT-5 Pro (4.1× as much).
Which scores higher on benchmarks?
Claude Opus 5 scores higher on the Capabilities Index (ECI): Claude Opus 5 162.9 (#5 of 148), GPT-5 Pro 150.3 (#46 of 148) and Claude Opus 4.5 150.1 (#48 of 148). Their confidence ranges do not overlap (160.2–166.7 vs 148.5–152.8), so the gap is a real one. On individual benchmarks: FrontierMath Tiers 1–3 — Claude Opus 5 85.6%, GPT-5 Pro 55.8%, Claude Opus 4.5 34.4%.
Which is better for coding?
There are no published SWE-bench Verified results for GPT-5 Pro and Claude Opus 5 yet, so there is no like-for-like coding score. On overall capability, Claude Opus 5 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?
Claude Opus 5 has the largest context window at 1,000,000 tokens, against 400,000 for GPT-5 Pro and 200,000 for Claude Opus 4.5. Maximum output per response: GPT-5 Pro up to 272,000, Claude Opus 5 up to 128,000, Claude Opus 4.5 up to 64,000 tokens.
Which can read images, PDFs, audio or video?
GPT-5 Pro accepts text and images; Claude Opus 5 accepts text, images and PDFs; Claude Opus 4.5 accepts text, images and PDFs. Claude Opus 5 handles the widest range of inputs.
Are any of these open source?
No. GPT-5 Pro, Claude Opus 5 and Claude Opus 4.5 are proprietary and only available through APIs and apps.
Which is newer?
Claude Opus 5 is the newest, released Jul 24, 2026. Claude Opus 4.5 came out Nov 24, 2025; GPT-5 Pro came out Oct 6, 2025. Knowledge cutoff: GPT-5 Pro Sep 30, 2024, Claude Opus 5 May 2026, Claude Opus 4.5 May 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.
