Skip to main content
AI Choice Engine

Model comparison

Claude Opus 5 vs Grok 4.6

Anthropic against SpaceXAI, compared on context, price, and attributed benchmark results.

Recorded profile verification October 1, 2026Individual provider fields may changeEvidence confidence: Medium — see receipts below

Anthropic

Claude Opus 5

Frontier

vs

SpaceXAI

Grok 4.6

Frontier

AI model capability comparison
SpecificationClaude Opus 5Grok 4.6
ProviderAnthropicSpaceXAI
TierFrontierFrontier
Context windowWinner: 1M500K
Max output128KNot verifiedUnverified
Input / 1M tokens$5Winner: $2
Output / 1M tokens$25Winner: $6
WeightsClosedClosed
ParametersNot verifiedUnverifiedNot verifiedUnverified
Reasoning levelslow, medium, high, xhigh, maxlow, medium, high, xhigh
Modalitiestext, imagetext, image
API model idclaude-opus-5grok-4.6
ReleasedJuly 24, 2026August 12, 2026
Humanity's Last Exam · source date Claude Opus 5: 2026-09-0163.6Not verifiedUnverified
Terminal-Bench 2.1 · source date Claude Opus 5: 2026-09-0289.1Not verifiedUnverified

Dates beside benchmark scores refer to the linked source’s publication or capture date unless that source explicitly states when it measured the result. A shared URL alone does not establish comparable runs; unverified setups are marked. Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.

Benchmark receipts

Where each score comes from, and how far it can be compared across models.

Pricing tiers

Claude Opus 5: Standard $5/$25 per MTok with no long-context surcharge. Cache reads $0.50; 5-minute writes $6.25 and 1-hour writes $10. Batch $2.50/$12.50. First-party Fast research preview $10/$50, unavailable with Batch. US-only inference adds 10% where supported. Batch 300K output requires output-300k-2026-03-24; standard stays 128K. Knowledge cutoff May 2026; retirement not sooner than July 24, 2027.

Grok 4.6: Standard $2/$6 per MTok below 200K prompt tokens; at 200K or more the full request bills $4/$12. Cached input $0.50 short or $1 long. US regional inference adds 10%. The published context is 500K; a separate text-output cap remains unverified.

FrontierRecord checked October 1, 2026

Claude Opus 5

Claude Opus 5 is Anthropic's July 2026 agentic-coding model, now 'Active (legacy)'. Its successor Opus 5.5 has lower base input/output prices ($4/$20 vs $5/$25 per million tokens); performance depends on the workload and evaluation settings.

Best for

  • Complex agentic coding
  • Enterprise work
  • Long-context analysis

Watch out

Active legacy, superseded by Opus 5.5. Test migration: Opus 5.5 makes adaptive thinking always on, rejects forced tool use and the older computer-use tool, and changes thinking-block/progress behavior. Partner cloud lifecycles and prices can differ.

FrontierRecord checked October 1, 2026

Grok 4.6

Grok 4.6 was xAI's August 2026 coding flagship, superseded by Grok 4.7 (2026-09-21) at the same $2/$6 price.

Best for

  • Coding agents
  • Chat and knowledge
  • Cost-sensitive frontier work

Watch out

An earlier API model, still listed in pricing. Current selection docs recommend Grok 4.7 at the same Standard base rates. Long-context billing starts at 200K inclusive. Effort defaults high and cannot be disabled; unsupported reasoning parameters can error.

When the cheaper one wins

Grok 4.6 is cheaper on output at $6 per million tokens against $25 for Claude Opus 5 — about 4.2×. Use the cheaper tier for classification, extraction, summarisation, and any task where the expensive model’s extra score does not change the accepted output. The expensive one only pays if your hardest task actually fails on the cheap tier. On DeepSWE 1.1, Grok 4.6 is 67.5% Pass@1 at $3.45/task versus Claude Opus 5 at 73.6% / $11.84/task. This compares standard short-context token rates, not total cost per accepted task. Include input, cache, context tiers, schedules, retries and review in your pilot.

Run the model picker

Evidence confidence: Medium

How strong and complete the evidence behind this comparison is — not a prediction of which model is better.

  • Pricing verified on both sides — Input and output rates are verified for both models.
  • 3/5 core specs verified on both sides — Not published for at least one side: max output, parameter count.
  • No directly aligned benchmark setup — No benchmark has matching cited sources, source dates, units, effort and recorded run details on both models.
  • Verified within the last 90 days — Older of the two catalog checks was 25 days ago.
  • Both models carry source citations — Each side has at least two catalog sources on record.

Source receipts

Each catalog figure was checked against the provider or an independent second source on the date shown.

Related comparisons

Diving deeper on one model? Claude Opus 5 · Grok 4.6

Common questions

Claude Opus 5 vs Grok 4.6

Answered from the verified figures on this page rather than general guidance.

Is Claude Opus 5 or Grok 4.6 cheaper for input?
Grok 4.6 is cheaper at $2 per million input tokens, against $5 for Claude Opus 5 — roughly 2.5× the price. Estimate both input and output token volume for your workload. These are base rates; Claude Opus 5: Standard $5/$25 per MTok with no long-context surcharge. Cache reads $0.50; 5-minute writes $6.25 and 1-hour writes $10. Batch $2.50/$12.50. First-party Fast research preview $10/$50, unavailable with Batch. US-only inference adds 10% where supported. Batch 300K output requires output-300k-2026-03-24; standard stays 128K. Knowledge cutoff May 2026; retirement not sooner than July 24, 2027. Grok 4.6: Standard $2/$6 per MTok below 200K prompt tokens; at 200K or more the full request bills $4/$12. Cached input $0.50 short or $1 long. US regional inference adds 10%. The published context is 500K; a separate text-output cap remains unverified.
Is Claude Opus 5 or Grok 4.6 cheaper for output?
Grok 4.6 is cheaper at $6 per million output tokens, against $25 for Claude Opus 5 — roughly 4.2× the price. Estimate both input and output token volume for your workload. These are base rates; Claude Opus 5: Standard $5/$25 per MTok with no long-context surcharge. Cache reads $0.50; 5-minute writes $6.25 and 1-hour writes $10. Batch $2.50/$12.50. First-party Fast research preview $10/$50, unavailable with Batch. US-only inference adds 10% where supported. Batch 300K output requires output-300k-2026-03-24; standard stays 128K. Knowledge cutoff May 2026; retirement not sooner than July 24, 2027. Grok 4.6: Standard $2/$6 per MTok below 200K prompt tokens; at 200K or more the full request bills $4/$12. Cached input $0.50 short or $1 long. US regional inference adds 10%. The published context is 500K; a separate text-output cap remains unverified.
Which has the larger context window, Claude Opus 5 or Grok 4.6?
Claude Opus 5 accepts 1M tokens against 500K for Grok 4.6. This only matters if you routinely send very long documents or large codebases.
Do Claude Opus 5 and Grok 4.6 support the same reasoning levels?
Claude Opus 5 exposes low, medium, high, xhigh, max, while Grok 4.6 exposes low, medium, high, xhigh.
Should I use Claude Opus 5 or Grok 4.6?
Both are classified in our frontier tier; this editorial grouping does not imply equal capability. Claude Opus 5 is a candidate for complex agentic coding; Grok 4.6 is a candidate for coding agents. Compare accuracy, tool reliability, latency and cost on representative tasks.

Next step

Choosing between them

The verified figures that separate this pair, computed from the catalog rather than restated boilerplate.

  • Input price: Grok 4.6 costs $2 per 1M tokens versus $5 for Claude Opus 5 — a 2.5x difference at the headline tier.
  • Context: Claude Opus 5 takes 1M against 500K for Grok 4.6 — only decisive if your prompts approach the smaller window.
Run the model pickerEstimate stack costAll model comparisons

Choosing a harness rather than a model — Cursor, Copilot, Claude Code, Windsurf, or Lovable? Compare agentic harnesses · Latest releases.