Skip to content
ModelCap

Head-to-head comparison

Claude Opus 5 vs Grok 4.6

Claude Opus 5 (Anthropic) and Grok 4.6 (xAI) compared on the ModelCap Index, API price, context window, provider availability, weight access and every public benchmark board they share. Figures are the same ones shown on the live rankings; nothing here is a hidden score.

Snapshot as of 17 August 2026

As of 17 August 2026, Claude Opus 5 holds the stronger ModelCap Index position (#2 vs #10); Grok 4.6 is 4.2× cheaper per output token ($6.00/1M vs $25.00/1M); and Claude Opus 5 offers the longer context window (1M vs 500K tokens).

Which should you choose?

Choose Claude Opus 5 if…

  • you want the stronger overall ModelCap Index position — #2 against #10 (83.1 vs 74.4 points).
  • you need the longer context window — 1M tokens against 500K.
  • you want provider choice — 5 listed API providers against 1.
  • Arena coding is your yardstick — 1531 against 1512.
  • ARC-AGI-2 is your yardstick — 90.4% against 67.1%.
  • ARC-AGI-3 is your yardstick — 30.2% against 2.1%.
  • Artificial Analysis Intelligence Index is your yardstick — 63.1 against 60.9.

Choose Grok 4.6 if…

  • API cost matters — $6.00/1M output tokens against $25.00/1M, about 4.2× cheaper.
  • your workload is prompt-heavy — input tokens cost $2.00/1M against $5.00/1M.
  • you want the more recently listed model — Grok 4.6 was listed 12 August 2026, Claude Opus 5 24 July 2026.

Claude Opus 5 vs Grok 4.6: specs, pricing and context

Specification comparison of Claude Opus 5 and Grok 4.6
FieldClaude Opus 5AnthropicGrok 4.6xAI
ModelCap Index position#2#10
Index score83.174.4
EvidenceMeasuredMeasured
Input price / 1M tokens$5.00$2.00
Output price / 1M tokens$25.00$6.00
Context window1M tokens500K tokens
Max output tokens128K—
API providers listed51
Weight accessAPI onlyAPI only
Input modalitiesText, Image, FileText, Image, File
First listed24 July 202612 August 2026
PublisherAnthropicxAI

Evidence: 6 public benchmark observations across 6 boards · 5 public benchmark observations across 5 boards. Prices are the lowest listed API offer per million tokens observed on the OpenRouter catalogue.

Benchmark scores: Claude Opus 5 vs Grok 4.6

Public benchmark boards where Claude Opus 5 or Grok 4.6 has a published result
BoardClaude Opus 5Grok 4.6Leads
Arena codingArena (LMArena)15311522–1540High15121485–1538HighClaude Opus 5
LMArena AgentLMArena12.2%10.7%–13.6%High—Only one result
ARC-AGI-2ARC Prize Foundation90.4%Max67.1%X-HighClaude Opus 5
ARC-AGI-3ARC Prize Foundation30.2%High2.1%X-HighClaude Opus 5
Artificial Analysis Intelligence IndexArtificial Analysis63.1intelligence-index60.9intelligence-indexClaude Opus 5

Scores are the sources' own published figures for each model's best evaluated configuration; ModelCap never re-runs a benchmark.

Want a different pairing? Open the interactive comparison tool to swap either model for any current ranked language model.

Claude Opus 5 vs Grok 4.6: common questions

Is Claude Opus 5 better than Grok 4.6?

Claude Opus 5 ranks higher on the ModelCap Index as of 17 August 2026: #2 against #10. That is a capability ranking built from public benchmark evidence with published uncertainty; whether it is "better" for you also depends on price, context and where you can run it.

Is Claude Opus 5 cheaper than Grok 4.6?

Grok 4.6 is cheaper on output tokens: $6.00/1M against $25.00/1M. Input tokens are $5.00/1M for Claude Opus 5 and $2.00/1M for Grok 4.6. Prices are the lowest listed API offer ModelCap observed, in USD per million tokens.

Which has the bigger context window, Claude Opus 5 or Grok 4.6?

Claude Opus 5 has the larger context window: 1M tokens against 500K.

Which is better for coding, Claude Opus 5 or Grok 4.6?

Arena coding: Claude Opus 5 1531, Grok 4.6 1512 — Claude Opus 5 leads.

Are Claude Opus 5 and Grok 4.6 open-weight models?

Claude Opus 5: API only. Grok 4.6: API only. Open weights mean the checkpoint can be downloaded and self-hosted under its licence; API-only models are available solely through hosted endpoints.

Where can I run Claude Opus 5 and Grok 4.6?

ModelCap currently lists 5 API providers for Claude Opus 5 and 1 for Grok 4.6, from the OpenRouter catalogue snapshot the site serves; each model page lists the providers and their prices.

How current is this Claude Opus 5 vs Grok 4.6 comparison?

Every figure comes from the sealed ModelCap dataset published 17 August 2026; the page re-renders within a minute of each data refresh, and the ModelCap Index positions are the same ones shown on the live rankings.

Explore further