Grok 3 vs Claude Opus 4.7 vs Gemini 3.1 Pro: 2026 Benchmark Breakdown
Quick verdict
This isn't a close race anymore. Claude Opus 4.7 dominates on intelligence and agent tasks. Gemini 3.1 Pro is faster than either and significantly cheaper. Grok 3 — released in February 2025 — is now over a year old and outclassed on nearly every intelligence benchmark, though it still holds its own in pure math.
If you want the short version: use Claude for complex reasoning and autonomous agents, Gemini for production workloads where cost and latency matter, and Grok only if you're specifically doing competitive math or want real-time X data integration.
The numbers
| Metric | Grok 3 (xAI) | Claude Opus 4.7 | Gemini 3.1 Pro |
|---|---|---|---|
| Intelligence Index | 25.2 | 57.3 | 57.2 |
| Coding Index | 19.8 | 52.5 | — |
| GPQA (grad-level science) | 69.3% | 91.4% | — |
| HLE (Humanity's Last Exam) | 5.1% | 39.6% | — |
| MMLU Pro | 79.9% | — | — |
| MATH 500 | 87.0% | — | — |
| AIME 2025 | 58.0% | — | — |
| TAU-bench v2 (agents) | 48.8% | 88.6% | — |
| TerminalBench Hard | 11.4% | 51.5% | — |
| Input cost / 1M tokens | $3.00 | $6.25 | $2.00 |
| Output cost / 1M tokens | $15.00 | $25.00 | $12.00 |
| Speed (tokens/sec) | 46 | 61 | 131 |
| Context window | ∞ | 1M | 1M |
| Released | Feb 2025 | Apr 2026 | Feb 2026 |
Source: LLMBase.ai intelligence indices via Artificial Analysis. Data as of May 2026.
What these benchmarks actually mean
The Intelligence Index (25.2 vs 57.3 vs 57.2) is the headline number, and it tells the real story. Claude and Gemini are operating at basically the same intelligence tier. Grok 3 is sitting roughly 2.3x lower — not because xAI builds bad models, but because Grok 3 is 15 months old and the frontier has moved on. Grok 4.3 is already on the leaderboard at a much higher score.
The GPQA score is worth pausing on. Claude Opus 4.7 at 91.4% on graduate-level science questions is genuinely extraordinary — that's PhD-level reasoning on chemistry, physics, and biology. Grok 3 at 69.3% is not bad, but it's not in the same conversation.
The HLE score is where Claude separates itself completely. Humanity's Last Exam is the hardest benchmark available — questions designed to stump the best human experts in their respective fields. Grok 3 scores 5.1%. Claude Opus 4.7 scores 39.6%. That's a 7x gap.
Where Grok 3 still holds up: MATH 500 (87%) and AIME 2025 (58%). If your use case is competitive math competitions or symbolic reasoning, Grok 3 isn't embarrassing.
Speed and cost: Gemini's case
Gemini 3.1 Pro doesn't get enough credit for what it does on the cost and speed axis. At 131 tokens per second, it's generating output more than twice as fast as Claude (61 tok/s) and nearly three times faster than Grok 3 (46 tok/s). For anything interactive — live chat, streaming responses, real-time applications — that gap is noticeable in practice.
The pricing is equally striking. At $2/1M input and $12/1M output, Gemini 3.1 Pro costs less than a third of Claude Opus 4.7 per token, while sitting at essentially the same intelligence level (57.2 vs 57.3). For teams watching their AI spend, that's a serious argument for routing general-purpose tasks through Gemini.
Where each model actually wins
Claude Opus 4.7
Complex reasoning that requires depth. Research synthesis, legal document analysis, scientific literature review. The agent tasks are where Claude has pulled furthest ahead — TAU-bench v2 at 88.6% and TerminalBench Hard at 51.5% are benchmarks that test real autonomous workflow execution, not just question-answering. If you're running AI agents for multi-step tasks, Claude is the clear choice right now.
Gemini 3.1 Pro
High-volume production workloads. Any application where you're paying per token at scale, or where response latency affects user experience. Gemini's 131 tok/s throughput combined with frontier-level intelligence makes it the rational default for most production API use cases. Also worth noting: Google's infrastructure means it scales cleanly without rate-limit headaches that plague some providers.
Grok 3
Competitive math and anything that benefits from access to X (Twitter) data in real time. Grok 3 is integrated with xAI's real-time X feed, which gives it a meaningful edge for anything involving current events, social media trends, or market sentiment. That said, Grok 4.3 is already available and significantly more capable — if you're on the xAI ecosystem, upgrade rather than staying on Grok 3.
Watch: 2026 AI model comparison
This breakdown covers how the major AI models stack up on real tasks in 2026, including Grok, Claude, and Gemini:
The subscription math
Here's the problem with picking one: each model has a different ceiling. Claude wins on reasoning, Gemini wins on cost, Grok wins on math and real-time data. The serious users who run benchmarks professionally typically use 2-3 models routed by task type.
The consumer subscription route gets expensive fast. Claude Pro is $20/mo. Gemini Advanced is $19.99/mo. X Premium for Grok API access is another subscription. That's $60/month before you've even run a single query.
Admix solves this by giving you all three — plus 70+ other models including GPT-5.5 and DeepSeek V4 — from a single plan starting at $8/month. You can run Grok 3 and Claude Opus 4.7 side by side on the same prompt and see exactly where each one differs. That comparison is how you actually learn which model fits which task in your workflow.
FAQ
Is Grok 3 still worth using in 2026?
For most use cases, no — it's been superseded by Claude Opus 4.7 and Gemini 3.1 Pro on intelligence metrics, and by Grok 4.3 within xAI's own lineup. The exceptions are competitive math benchmarks and real-time X data integration, where Grok still has specific advantages.
Is Claude Opus 4.7 worth the price premium over Gemini?
If you're running autonomous agents, yes. The TAU-bench and TerminalBench gaps are substantial and reflect real capability differences in multi-step task execution. For general chat and document analysis where both models score similarly on intelligence, Gemini's 3x price advantage is hard to justify passing up.
Which model is best for coding?
Claude Opus 4.7 leads on the Coding Index (52.5 vs Grok's 19.8). See the full coding model comparison for task-specific breakdowns including LiveCodeBench and SWE-bench scores.
How fast do these models actually respond?
Gemini 3.1 Pro is by far the fastest at 131 tokens/second. In practical terms, for a 500-word response, Gemini finishes in about 15 seconds where Claude takes 26 seconds and Grok takes 35 seconds. That difference matters in interactive applications.
Sources
- LLMBase.ai — Grok 3 vs Claude Opus 4.7 comparison (May 2026)
- LLMBase.ai — Grok 3 vs Gemini comparison (May 2026)
- Artificial Analysis — Intelligence Index methodology
Further Reading
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