Claude 4 Sonnet vs Grok 4.3
Head-to-head specifications
| Metric | Claude 4 Sonnet | Grok 4.3 | Difference |
|---|---|---|---|
| Intelligence Index | 29.0 | 38.0 | -23.7% |
| Coding Index | 37.6 | 42.2 | -10.9% |
| Agentic Index | 16.6 | 24.1 | — |
| Context window | 1M tokens | 1M tokens | — |
| Blended price ($/1M tokens) | $1.20 | $0.52 | +130.8% |
| Access | Proprietary API | Proprietary API | — |
- Grok 4.3 leads overall capability (Intelligence Index 38.0 vs 29.0).
- Grok 4.3 is the cheaper model to run at $0.52/1M blended tokens — about 2.3× cheaper.
Verdict: Claude 4 Sonnet or Grok 4.3?
Claude 4 Sonnet advantages
- No decisive advantage on the tracked metrics.
Grok 4.3 advantages
- General intelligence (+24%)
- Coding ability (+11%)
- Agentic task performance (+31%)
- Affordability (+57%)
Which should you choose?
- Choose the Grok 4.3 if you need the strongest overall reasoning and accuracy.
Value for money
Grok 4.3 offers more intelligence per dollar (3.0× the Intelligence-Index-per-cost of the alternative), making it the stronger value for high-volume use.
Claude 4 Sonnet vs Grok 4.3: which should you choose?
Claude 4 Sonnet — Anthropic multimodal model with an Intelligence Index of 29, a 1M-token context window and a blended price of $1.2/1M tokens.
Grok 4.3 — xAI multimodal model with an Intelligence Index of 38, a 1M-token context window and a blended price of $0.52/1M tokens.
Claude 4 Sonnet vs Grok 4.3: Grok 4.3 scores higher on the Intelligence Index. Grok 4.3 leads overall capability (Intelligence Index 38.0 vs 29.0). Grok 4.3 is the cheaper model to run at $0.52/1M blended tokens — about 2.3× cheaper.
Capability: intelligence, coding and agentic work
On the composite Intelligence Index the Grok 4.3 scores 38.0 versus 29.0. For software development, the Coding Index puts Grok 4.3 ahead (42.2 vs 37.6). On agentic, multi-step tool-use tasks, Grok 4.3 measures stronger. Composite indices summarize many evaluations, but always test on your own workload before committing.
Context window and speed
The Claude 4 Sonnet accepts up to 1 million tokens per request, which sets how much documentation, transcript or code it can reason over at once.
Pricing and access
At blended per-token rates, Grok 4.3 is the cheaper model to run ($0.52 vs $1.20 per 1M tokens). Claude 4 Sonnet is proprietary api and Grok 4.3 is proprietary api. Open-weight models can be self-hosted, trading per-call cost for infrastructure you manage; for production also weigh rate limits, throughput and data-residency requirements.
The verdict
Both are credible choices in the ai model comparison space; the specification table above lays out every metric so you can weigh the trade-offs that matter to you. Pick the one whose strengths line up with how you will actually use it.
Frequently asked questions
Is the Claude 4 Sonnet better than the Grok 4.3?
Grok 4.3 is the clearly stronger overall choice, winning most of the dimensions that matter. Grok 4.3 leads overall capability (Intelligence Index 38.0 vs 29.0).
What is the main difference between the Claude 4 Sonnet and the Grok 4.3?
Grok 4.3 leads overall capability (Intelligence Index 38.0 vs 29.0). Grok 4.3 is the cheaper model to run at $0.52/1M blended tokens — about 2.3× cheaper.
Which is better value?
Grok 4.3 offers more intelligence per dollar (3.0× the Intelligence-Index-per-cost of the alternative), making it the stronger value for high-volume use.
Which should I choose?
Choose the Grok 4.3 if you need the strongest overall reasoning and accuracy.
Methodology
Large language models are compared on independent leaderboard metrics: an Intelligence Index (a composite of reasoning and knowledge evaluations), Coding and Agentic indices where measured, community arena Elo, maximum context window, a blended API price per million tokens (weighted across cache-hit, input and output rates), and measured output speed in tokens per second. Where a model ships multiple reasoning-effort variants, we report its strongest variant. Benchmarks capture only part of real-world quality, which also depends on tool use, latency, safety and task fit — and this space moves quickly, so figures reflect the leaderboard snapshot on the page date.