Claude Opus 5 vs Grok 4.5
Side-by-side comparison of API pricing, specs, benchmarks, and capabilities
| Specification |
by Anthropic
|
by xAI
|
|---|---|---|
| Overview | ||
| Status | Current flagship | Current flagship |
| Released | ||
| Pricing per million tokens | ||
| Input | $5.00/Mtok | $2.00/Mtok |
| Output | $25.00/Mtok | $6.00/Mtok |
| Blended avg | $10.00/Mtok | $3.00/Mtok |
| Cached input | $0.500/Mtok | — |
| Specifications | ||
| Context window | 1M tokens | 500K tokens |
| Parameters | Proprietary | Proprietary |
| Speed (TPS) | — | — |
| Modalities | ||
| Input |
textimage
|
textimage
|
| Benchmarks sources: Vellum LLM Leaderboard / Artificial Analysis, LMSYS Chatbot Arena (UC Berkeley), xAI Grok 4.5 launch post | ||
| Independent composite scores measured for both models — each on its own scale | ||
| AA Intelligence Index | 50.7 | 39.1 |
| AA Agentic Index | 56.2 | 42.1 |
| AA-Omniscience Index (−100–100) | 37.1 | 25.3 |
| GDPval-AA v2 | 1735.1 ELO | 1526.4 ELO |
| LMSYS Chatbot Arena | — | 1469 ELO |
| Per-benchmark results no per-benchmark score is published for both models — the composites above are what compares them | ||
| Avg benchmark score | 84.2 | — |
| Perf / dollar | 8.4 | — |
| SWE-Bench Verified | 97 | — |
| Terminal-Bench 2.1 | — | 83.3 vendor |
| BrowseComp | 90.8 | — |
| Humanity's Last Exam | 64.7 | — |
| AutoBench | 26 | — |
| Providers | ||
| Available from |
Anthropic — $5.00/$25.00/Mtok
|
xAI — $2.00/$6.00/Mtok
|
Cost at scale
1M tokens · 50/50 input/output| Volume | Claude Opus 5 | Grok 4.5 | Savings |
|---|---|---|---|
| 1M tokens | $10 | $3 | $7 (70%) |
| 10M tokens | $100 | $30 | $70 (70%) |
| 100M tokens | $1000 | $300 | $700 (70%) |
| 1000M tokens | $10000 | $3000 | $7000 (70%) |
When to pick which
distilled from the pricing and spec data above- your workload re-reads context (agents, RAG, long chats): cached input costs $0.500/Mtok — 90% off its list input price, a discount Grok 4.5 doesn't offer
- you need the longer context: 1M tokens vs 500K (2×)
- cost dominates: $3.00/Mtok blended vs $10.00 — 70% less on the same 50/50 token mix
The cheaper option here — Grok 4.5 costs $3.00/Mtok blended on xAI.
Summary
Claude Opus 5 by Anthropic costs $5.00/Mtok input and $25.00/Mtok output, with a 1M-token context window. It supports text, image input.
Grok 4.5 by xAI costs $2.00/Mtok input and $6.00/Mtok output, with a 500K-token context window. It supports text, image input.
On a blended cost basis, Grok 4.5 is 70% cheaper than Claude Opus 5.
The two aren't directly comparable on average benchmark score: Claude Opus 5 has published per-benchmark results, while Grok 4.5 does not yet — it is measured today on independent composites (see the table above).
Note: Pricing is per million tokens. Actual costs vary with usage patterns, prompt caching, and batch discounts. Always verify against official provider pricing pages.