Claude Opus 4.6 (2026-02-05) vs Grok 4.20 Multi Agent beta 0309

Claude Opus 4.6 (2026-02-05) (Anthropic, 1,000,000-token context) versus Grok 4.20 Multi Agent beta 0309 (xAI, 2,000,000-token context). Grok 4.20 Multi Agent beta 0309 is cheaper by 73% on a blended token mix. Claude Opus 4.6 (2026-02-05) uniquely supports pdf input and structured output (json schema). Across 1 public benchmark we tracked, Claude Opus 4.6 (2026-02-05) wins 1 and Grok 4.20 Multi Agent beta 0309 wins 0. Use the live calculator below to plug your real usage shape into both, then route the winner via Agent Command Center for shadow A/B without code changes.

Bottom line — Claude Opus 4.6 (2026-02-05) vs Grok 4.20 Multi Agent beta 0309

Claude Opus 4.6 (2026-02-05) and Grok 4.20 Multi Agent beta 0309 target overlapping workloads but differ sharply on economics. Grok 4.20 Multi Agent beta 0309 runs roughly 73% cheaper on a blended input-plus-output token mix, which translates to approximately $20,400 per month at mid-market volume (100K requests/day). The gap compounds at enterprise scale, making the cost axis the first filter most teams apply when deciding between these two models.

Grok 4.20 Multi Agent beta 0309 ships a 2,000,000-token context window, 2.0x larger than Claude Opus 4.6 (2026-02-05)'s 1,000,000 tokens. That headroom matters for long-document RAG pipelines, multi-turn agent sessions that accumulate tool-call history, and codebases where the entire repository needs to fit in a single prompt. If your average prompt stays under 1,000,000 tokens, the extra context on Grok 4.20 Multi Agent beta 0309 is insurance you may never use — and Claude Opus 4.6 (2026-02-05) may win on other axes.

On capability surface area, the models diverge: Claude Opus 4.6 (2026-02-05) supports pdf input where the other does not; Claude Opus 4.6 (2026-02-05) supports structured output (json schema) where the other does not. These differences are binary — either your workload needs the capability or it does not. Check whether any critical path in your agent pipeline depends on a capability only one model provides before committing to a migration.

For teams evaluating both models, the recommended path is a shadow A/B test: route production traffic through an OpenAI-compatible gateway, mirror a percentage to the candidate model, score both responses with an automated evaluator (faithfulness, tool-call correctness, latency), and compare cohort-level metrics over two weeks. Future AGI Agent Command Center supports this pattern with a single `base_url` change and built-in evaluators from the ai-evaluation SDK.

Side-by-side cost

Live workload comparison

Same workload run through both models. The cheaper one is highlighted.

3,000
02,000,000
400
0200,000
5,000
01,000,000
Anthropic
$3,805/mo
Input $5.00/M · Output $25.00/M
xAI
$1,278/mo
Input $2.00/M · Output $6.00/M
At this workload, Grok 4.20 Multi Agent beta 0309 is 66% cheaper than Claude Opus 4.6 (2026-02-05) — a savings of $2,526/month ($30,316/year).
Production recipe — Agent Command Center
strategy: cost-optimized
primary:
  model: grok-4-20-multi-agent-beta-0309
  provider: xai
fallback:
  model: claude-opus-4-6-20260205
  provider: anthropic
shadow: { sample_rate: 0.05 }   # mirror 5% of traffic to compare quality live
Claude Opus 4.6 (2026-02-05) Grok 4.20 Multi Agent beta 0309
xAI
Input price $5.00/M $2.00/M
Output price $25.00/M $6.00/M
Context window 1,000,000 2,000,000
Max output 128,000 2,000,000
Function calling
Vision
Audio input
Reasoning
Prompt caching
Structured output
Pricing verified Jun 2, 2026 Jun 2, 2026
Cheaper option
~73% cheaper than the priciest in this pair
Larger context
2,000,000 tokens
More capabilities
5 of 6 capability flags advertised

Benchmark comparison

Side-by-side public benchmark scores. Greener bar = winner.

Chatbot Arena ELOgeneral
Claude Opus 4.6 (2026-02-05)
1,498
Grok 4.20 Multi Agent beta 0309
1,473

Cost at scale: monthly spend at three usage volumes

Estimated monthly cost assuming 1,000 input + 200 output tokens per request — a realistic chat-agent shape. Adjust your own usage in the calculator at the top of this page for an exact number.

Scale Claude Opus 4.6 (2026-02-05) Grok 4.20 Multi Agent beta 0309 Delta
Startup
10K requests/day
$3,000 /mo $960 /mo $2,040/mo
Mid-market
100K requests/day
$30,000 /mo $9,600 /mo $20,400/mo
Enterprise
1M requests/day
$300,000 /mo $96,000 /mo $204,000/mo

At enterprise scale (1M requests/day), a difference of even ~10% in unit price compounds into thousands of dollars per month. Cached input pricing and batch tiers can shift this further — both are surfaced on each model's own page.

When to choose which

Picked from the data above — not vendor marketing. Match the rules to your workload, not the other way around.

Choose Grok 4.20 Multi Agent beta 0309

You're cost-sensitive at scale — Grok 4.20 Multi Agent beta 0309 runs ~73% cheaper on a blended in+out token mix, compounding into thousands of dollars per month at production volume.

Choose Grok 4.20 Multi Agent beta 0309

Your workload needs long context — Grok 4.20 Multi Agent beta 0309 fits 2,000,000 tokens versus the other model's 1,000,000, enough headroom for full books, large codebases, or 100+ page documents in one shot.

Choose Claude Opus 4.6 (2026-02-05)

On arena-elo, Claude Opus 4.6 (2026-02-05) scores 25.0 points higher — if your workload pattern matches that benchmark's task shape, the gap is meaningful.

Capability diff — what you gain and lose on the swap

A specific list of what each model has that the other doesn't. If your workload depends on a row in Only Claude Opus 4.6 (2026-02-05), switching to Grok 4.20 Multi Agent beta 0309 means re-architecting that path (and vice versa).

Only on Claude Opus 4.6 (2026-02-05)
  • • PDF input
  • • Structured output (JSON schema)
Only on Grok 4.20 Multi Agent beta 0309
Nothing — everything Grok 4.20 Multi Agent beta 0309 ships is also on Claude Opus 4.6 (2026-02-05).
Capabilities both share (5)
  • ✓ Function calling
  • ✓ Vision input
  • ✓ Streaming
  • ✓ Prompt caching
  • ✓ Native reasoning mode

Benchmark winners — by the numbers

For each public benchmark that has scores for both models, the higher score and the size of the gap. Benchmarks are noisy — treat anything under a 2-point delta as effectively tied.

Benchmark Claude Opus 4.6 (2026-02-05) Grok 4.20 Multi Agent beta 0309 Winner Δ
arena-elo 1498.0 1473.0 Claude Opus 4.6 (2026-02-05) +25.0

Migration considerations

Concrete differences to wire through your stack before you flip traffic from one to the other.

  • Context window changes up 100% when moving from Claude Opus 4.6 (2026-02-05) (1,000,000) to Grok 4.20 Multi Agent beta 0309 (2,000,000). Re-check any prompt that relies on cramming long history or documents.
  • Max output tokens differ: 128,000 on Claude Opus 4.6 (2026-02-05) vs 2,000,000 on Grok 4.20 Multi Agent beta 0309. Long-form generation tasks may truncate differently — adjust streaming UI and chunking accordingly.
  • Claude Opus 4.6 (2026-02-05) has capabilities Grok 4.20 Multi Agent beta 0309 lacks: PDF input, Structured output (JSON schema). Switching to Grok 4.20 Multi Agent beta 0309 means re-architecting any flow that depends on these.
  • Provider changes from Anthropic to xAI. API authentication, rate-limit policy, regional availability, and billing all shift. Most teams route through an OpenAI-compatible gateway (e.g., Future AGI Agent Command Center) so the swap is a single `base_url` change instead of an SDK rewrite.

How to A/B test Claude Opus 4.6 (2026-02-05) vs Grok 4.20 Multi Agent beta 0309 in production

If you're stuck between the two, run them side-by-side on real traffic. Four steps the Future AGI team uses internally:

  1. 1. Point your existing OpenAI SDK at https://gateway.futureagi.com/v1. No code change beyond base_url and a virtual key.
  2. 2. Mark Claude Opus 4.6 (2026-02-05) primary, mirror 20% of traffic to Grok 4.20 Multi Agent beta 0309 in shadow mode. Both responses are logged; only the primary is served to users.
  3. 3. Score every shadow response with an evaluator — faithfulness, tool-call correctness, response latency, cost. Built-in evaluators in ai-evaluation cover the common axes.
  4. 4. Compare cohort-level metrics after two weeks. Switch primary when the candidate wins on what matters to your workload — and stays within your latency budget.

Full walkthrough on the Agent Command Center page.

FAQ — Claude Opus 4.6 (2026-02-05) vs Grok 4.20 Multi Agent beta 0309

Which is cheaper, Claude Opus 4.6 (2026-02-05) or Grok 4.20 Multi Agent beta 0309?

Grok 4.20 Multi Agent beta 0309 is cheaper by roughly 73% on a blended input + output token mix. Input prices are $5.00/M for Claude Opus 4.6 (2026-02-05) versus $2.00/M for Grok 4.20 Multi Agent beta 0309; output prices are $25.00/M versus $6.00/M. The exact savings depend on your input:output ratio — use the live calculator above to plug in your own request shape.

What is the context window of Claude Opus 4.6 (2026-02-05) versus Grok 4.20 Multi Agent beta 0309?

Claude Opus 4.6 (2026-02-05) supports up to 1,000,000 tokens of context. Grok 4.20 Multi Agent beta 0309 supports up to 2,000,000 tokens. Grok 4.20 Multi Agent beta 0309 has the larger window by a factor of 2.0x, which matters for long-document RAG, multi-turn agent sessions, and tasks that need to keep an entire codebase in working memory.

Do Claude Opus 4.6 (2026-02-05) and Grok 4.20 Multi Agent beta 0309 both support tool calling?

Yes — both Claude Opus 4.6 (2026-02-05) and Grok 4.20 Multi Agent beta 0309 support native function calling. Both also support structured output via JSON schema, so an agent can be ported between them with the same tool definitions.

Which model supports prompt caching for cost reduction?

Both Claude Opus 4.6 (2026-02-05) and Grok 4.20 Multi Agent beta 0309 support prompt caching. Cached input tokens are typically discounted 50–90% versus uncached input, depending on the provider. For agents with a stable system prompt + retrieval context, the cached pricing tier is the real unit economics number to track.

When should I choose Claude Opus 4.6 (2026-02-05) over Grok 4.20 Multi Agent beta 0309?

On arena-elo, Claude Opus 4.6 (2026-02-05) scores 25.0 points higher — if your workload pattern matches that benchmark's task shape, the gap is meaningful.

When should I choose Grok 4.20 Multi Agent beta 0309 over Claude Opus 4.6 (2026-02-05)?

You're cost-sensitive at scale — Grok 4.20 Multi Agent beta 0309 runs ~73% cheaper on a blended in+out token mix, compounding into thousands of dollars per month at production volume. Your workload needs long context — Grok 4.20 Multi Agent beta 0309 fits 2,000,000 tokens versus the other model's 1,000,000, enough headroom for full books, large codebases, or 100+ page documents in one shot.

How do I A/B test Claude Opus 4.6 (2026-02-05) against Grok 4.20 Multi Agent beta 0309 in production?

Route both through an OpenAI-compatible gateway like Future AGI Agent Command Center with shadow mode enabled. Send 100% of traffic to your primary model, mirror 10–20% to the candidate, score every response with an evaluator (faithfulness, tool-call correctness, response time), and compare cohort-level metrics for two weeks. Switch when the candidate wins on the metrics that matter to your workload and stays within your latency budget.