Grok 4.3 vs Claude Opus 5 vs GPT-5.4 mini
Too close to call on our weighted score (Grok 4.3 67, Claude Opus 5 66, GPT-5.4 mini 63). The right pick depends on what you value most.
xAIGrok 4.3
67/100- ECI149.2
- Price$1.25 / $2.50
- Context1M
AnthropicClaude Opus 5
66/100- ECI162.9
- Price$5.00 / $25.00
- Context1M
OpenAIGPT-5.4 mini
63/100- ECI148.8
- Price$0.75 / $4.50
- Context400K
Too close to call
It is close. Our weighted score puts them within a point (Grok 4.3 67/100, Claude Opus 5 66/100, GPT-5.4 mini 63/100), so choose by what matters most for your work: Claude Opus 5 for raw capability and Grok 4.3 on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
- CapabilityClaude Opus 5Capabilities Index (ECI): Claude Opus 5 162.9 · Grok 4.3 149.2 · GPT-5.4 mini 148.8
- Lowest priceGrok 4.3Grok 4.3 $1.56 · GPT-5.4 mini $1.69 · Claude Opus 5 $10.00 per 1M tokens (3:1 blend)
- Longest contextGrok 4.3 and Claude Opus 5Grok 4.3 1,000,000 · Claude Opus 5 1,000,000 · GPT-5.4 mini 400,000 tokens
- Widest inputsGrok 4.3 and Claude Opus 5Grok 4.3: Text, Images, PDFs · Claude Opus 5: Text, Images, PDFs · GPT-5.4 mini: Text, Images
- Self-hostingNo open weightsAll three are available only through APIs
| Measure | Weight | Grok 4.3 | Claude Opus 5 | GPT-5.4 mini |
|---|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 50% | 77 | 94 | 77 |
| Price | 25% | 41 | 2 | 39 |
| Inputs & features | 15% | 80 | 80 | 70 |
| Context window | 10% | 60 | 60 | 44 |
| Overall | 100% | 67/100 | 66/100 | 63/100 |
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | Grok 4.3xAI | Claude Opus 5Anthropic | GPT-5.4 miniOpenAI |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | 149.2 | 162.9 (best) | 148.8 |
| ECI rank | #55 of 148 | #5 of 148 (best) | #56 of 148 |
| GPQA DiamondGraduate-level science questions | 88.8% | 93.9% (best) | 86.9% |
| FrontierMath Tiers 1–3Research-level mathematics | 42.8% | 85.6% (best) | 51.2% |
| OTIS Mock AIME 2024–2025Competition mathematics | 93.3% | 98.9% (best) | 88.9% |
| SimpleQA VerifiedShort factual questions | 33.2% | 59.9% (best) | 29.4% |
| Price per million tokens | |||
| Input | $1.25 | $5.00 | $0.75 (best) |
| Output | $2.50 (best) | $25.00 | $4.50 |
| Cached input | $0.20 | $0.50 | $0.075 (best) |
| Blended (3:1) | $1.56 (best) | $10.00 | $1.69 |
| Long-context rate | Over 200K: $2.50 / $5.00 | Same rate | Same rate |
| Price source | Official xAI API | Official Anthropic API | Official OpenAI API |
| Limits | |||
| Context window | 1,000,000 tokens (best) | 1,000,000 tokens (best) | 400,000 tokens |
| Max output | 30,000 tokens | 128,000 tokens (best) | 128,000 tokens (best) |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | Yes | Yes |
| PDFs | Yes | Yes | No |
| Audio | No | No | No |
| Video | No | No | No |
| Reasoning | Yeslow · medium · high | Yeslow · medium · high · xhigh · max | Yeslow · medium · high · xhigh |
| Tool calling | Yes | Yes | Yes |
| Structured output | Yes | Yes | Yes |
| Availability | |||
| Weights | Proprietary | Proprietary | Proprietary |
| API model ID | grok-4.3 | claude-opus-5 | gpt-5.4-mini |
| API providers | 27 | 35 (best) | 29 |
| Released | Apr 17, 2026 | Jul 24, 2026 | Mar 17, 2026 |
| Knowledge cutoff | — | May 2026 | Aug 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.
- Grok 4.3$17.50
- Claude Opus 5$100.00
- GPT-5.4 mini$16.50
Which should you choose?
Which is better: Grok 4.3, Claude Opus 5 or GPT-5.4 mini?
It is close. Our weighted score puts them within a point (Grok 4.3 67/100, Claude Opus 5 66/100, GPT-5.4 mini 63/100), so choose by what matters most for your work: Claude Opus 5 for raw capability and Grok 4.3 on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.
Which is cheaper, Grok 4.3, Claude Opus 5 or GPT-5.4 mini?
Grok 4.3 is cheaper at $1.25 input / $2.50 output per million tokens (official xAI API price). GPT-5.4 mini costs $0.75 input / $4.50 output per million tokens (official OpenAI API price); Claude Opus 5 costs $5.00 input / $25.00 output per million tokens (official Anthropic API price). At a typical mix of three input tokens to one output token, that is $1.56 per million tokens for Grok 4.3 versus $1.69 for GPT-5.4 mini (1.1× as much) and $10.00 for Claude Opus 5 (6.4× 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), Grok 4.3 149.2 (#55 of 148) and GPT-5.4 mini 148.8 (#56 of 148). Their confidence ranges do not overlap (160.2–166.7 vs 147.6–150.8), so the gap is a real one. On individual benchmarks: GPQA Diamond — Claude Opus 5 93.9%, Grok 4.3 88.8%, GPT-5.4 mini 86.9%; FrontierMath Tiers 1–3 — Claude Opus 5 85.6%, GPT-5.4 mini 51.2%, Grok 4.3 42.8%; OTIS Mock AIME 2024–2025 — Claude Opus 5 98.9%, Grok 4.3 93.3%, GPT-5.4 mini 88.9%; SimpleQA Verified — Claude Opus 5 59.9%, Grok 4.3 33.2%, GPT-5.4 mini 29.4%.
Which is better for coding?
There are no published SWE-bench Verified results for Grok 4.3, Claude Opus 5 and GPT-5.4 mini 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?
Grok 4.3 and Claude Opus 5 have the largest context windows (1,000,000 and 1,000,000 tokens), against 400,000 for GPT-5.4 mini. Maximum output per response: Grok 4.3 up to 30,000, Claude Opus 5 up to 128,000, GPT-5.4 mini up to 128,000 tokens.
Which can read images, PDFs, audio or video?
Grok 4.3 accepts text, images and PDFs; Claude Opus 5 accepts text, images and PDFs; GPT-5.4 mini accepts text and images. Grok 4.3 handles the widest range of inputs.
Are any of these open source?
No. Grok 4.3, Claude Opus 5 and GPT-5.4 mini are proprietary and only available through APIs and apps.
Which is newer?
Claude Opus 5 is the newest, released Jul 24, 2026. Grok 4.3 came out Apr 17, 2026; GPT-5.4 mini came out Mar 17, 2026. Knowledge cutoff: Claude Opus 5 May 2026, GPT-5.4 mini Aug 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.
