Grok 4.5 vs Claude Sonnet 5
Side-by-side comparison of API pricing, specs, benchmarks, and capabilities
| Specification |
by xAI
|
by Anthropic
|
|---|---|---|
| Overview | ||
| Status | Current flagship | Current mid tier |
| Released | Jul 8, 2026 | Jun 30, 2026 |
| Pricing per million tokens | ||
| Input | $2.00/Mtok | $2.00/Mtok |
| Output | $6.00/Mtok | $10.00/Mtok |
| Blended avg | $3.00/Mtok | $4.00/Mtok |
| Cached input | — | $0.200/Mtok |
| Price basis | — | Standard pricing, per 1M tokens — not a promotional rate. $2/$10 was announced at launch as introductory pricing through Aug 31 2026, but Anthropic's pricing page now states that it "is now the standard price" and that "the previously scheduled increase to $3/$15 per million input/output tokens on September 1, 2026 will not occur". There is therefore no reversion date to watch. Verified 2026-08-13 against platform.claude.com/docs/en/about-claude/pricing. |
| Specifications | ||
| Context window | 500K tokens | 1M tokens |
| Parameters | Proprietary | Proprietary |
| Speed (TPS) | — | — |
| Modalities | ||
| Input |
textimage
|
textimage
|
| Benchmarks sources: Artificial Analysis, LMSYS Chatbot Arena (UC Berkeley), xAI Grok 4.5 launch post / Vellum LLM Leaderboard | ||
| Terminal-Bench 2.1 | 83.3 vendor | 80.4 |
| Avg benchmark score | — | 81.5 |
| Perf / dollar | — | 20.4 |
| GPQA Diamond | — | 96.2 |
| SWE-Bench Verified | — | 85.2 |
| BrowseComp | — | 84.7 |
| OSWorld-Verified | — | 81.2 |
| Humanity's Last Exam | — | 57.4 |
| HumanEval | — | 85.2 |
| AutoBench | — | 13.5 |
| Independent composite scores each on its own scale — not part of the average above | ||
| AA Intelligence Index | 55.8 | 55.3 |
| AA Agentic Index | 48.9 | 49.7 |
| AA-Omniscience Index (−100–100) | 25.3 | 16.4 |
| GDPval-AA v2 | 1526.4 ELO | 1598.2 ELO |
| LMSYS Chatbot Arena | 1469.6 ELO | — |
| Providers | ||
| Available from |
xAI — $2.00/$6.00/Mtok
|
Anthropic — $2.00/$10.00/Mtok
|
Cost at scale
1M tokens · 50/50 input/output| Volume | Grok 4.5 | Claude Sonnet 5 | Savings |
|---|---|---|---|
| 1M tokens | $3 | $4 | $1 (25%) |
| 10M tokens | $30 | $40 | $10 (25%) |
| 100M tokens | $300 | $400 | $100 (25%) |
| 1000M tokens | $3000 | $4000 | $1000 (25%) |
When to pick which
distilled from the pricing and spec data above- cost dominates: $3.00/Mtok blended vs $4.00 — 25% less on the same 50/50 token mix
- your workload re-reads context (agents, RAG, long chats): cached input costs $0.200/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×)
The cheaper option here — Grok 4.5 costs $3.00/Mtok blended on xAI.
Summary
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.
Claude Sonnet 5 by Anthropic costs $2.00/Mtok input and $10.00/Mtok output, with a 1M-token context window. It supports text, image input.
On a blended cost basis, Grok 4.5 is 25% cheaper than Claude Sonnet 5.
The two aren't directly comparable on average benchmark score: Claude Sonnet 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.