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Anthropic vs xAI

Two closed labs with different bets: Anthropic on agentic coding and flat 1M pricing, xAI on cheap output tokens and live data from X. Long contexts expose the biggest pricing difference.

By The Subconscious Team · Updated

Anthropic vs xAI: key differences

Anthropic and xAI both sell closed models through first-party APIs, but their pricing handles long prompts very differently. Claude's top three tiers carry 1M context at standard rates with no surcharge past 200K. xAI's Grok 4.7 has a 500K window at $2 in and $6 out, and once a prompt hits 200K tokens the whole request bills at double. Older Grok 4.20 and 4.3 keep 1M context at $1.25 in and $2.50 out. On output-heavy work, xAI is much cheaper than Anthropic at comparable tiers, while Fable 5.1 always thinks and runs up output tokens.

xAI's distinct asset is data, not price. Server-side Web Search and X Search pull current posts straight from X, which suits news, market and social-sentiment agents. Anthropic's is coding: top SWE-bench Pro results, Claude Code's adoption, and availability on Bedrock, Vertex AI and Microsoft Foundry, where xAI has a smaller enterprise footprint and fewer marketplace options. xAI also has separate first-party APIs for image, video and audio. Long repo-scale agents fit Claude better. Fresh-data and cost-first reasoning tasks fit Grok.

What Anthropic and xAI do

Anthropic

Anthropic sells the Claude family of closed models through its own API, Amazon Bedrock, Google Vertex AI and Microsoft Foundry. The public lineup today runs from Claude Fable 5.1 at the top, released September 1, 2026, through Opus 5.5 ($4 in, $20 out) and Sonnet 5.5 ($2 in, $10 out) down to Haiku 5.5. List prices span a hundredfold range, from $10 in and $50 out on Fable to $0.10 in and $0.50 out on Haiku. All four tiers have a 1M token context window. The top three bill it at standard pricing, while Haiku 5.5 charges more past 100K.

Example models: Claude Fable 5.1, Claude Opus 5.5, Claude Haiku 5.5

Full Anthropic profile

xAI

xAI sells the Grok models through its own API. SpaceX acquired it in February 2026, and its docs now use the SpaceXAI name. Grok 4.7, released September 21, 2026, is the current flagship, pitched for coding, agentic tasks and knowledge work. It has a 500K context window and costs $2 in and $6 out per million tokens under 200K prompt tokens. Older Grok 4.20 and 4.3 models keep a 1M window at $1.25 in and $2.50 out, which is aggressive for that capability class.

Example models: Grok 4.7, Grok 4.20

Full xAI profile

Should you choose Anthropic or xAI?

Anthropic

Choose Anthropic for

  • Agent contexts past 200K without a doubling surcharge
  • Enterprise buyers who need the model on major clouds
  • Agentic coding and code review

xAI

Choose xAI for

  • Social listening and news agents that need live X data
  • Output-heavy reasoning where cheaper tokens matter
  • Teams that also want first-party image, video and audio APIs

Anthropic vs xAI at a glance

AttributeAnthropicxAI
Model accessClosedClosed
Flagship modelsClaude Fable 5.1, Opus 5.5, Sonnet 5.5, Haiku 5.5Grok 4.7, Grok 4.20, grok-build
SpeedFable is the slowest tier~54 tok/s on Grok 4.6
Price$0.10–$10 in, $0.50–$50 out per 1M$2 in, $6 out (Grok 4.7); 2x past 200K
CustomizationN/AUnknown
DeploymentAPI, Bedrock, Vertex AI, Microsoft FoundryFirst-party API
Long context1M; Haiku 5.5 costs more past 100K500K (4.7), 1M (4.20, 4.3)

Frequently asked questions

What is the difference between Anthropic and xAI?

Two closed labs with different bets: Anthropic on agentic coding and flat 1M pricing, xAI on cheap output tokens and live data from X. Long contexts expose the biggest pricing difference.

When should I choose Anthropic over xAI?

Agent contexts past 200K without a doubling surcharge; Enterprise buyers who need the model on major clouds; Agentic coding and code review.

When should I choose xAI over Anthropic?

Social listening and news agents that need live X data; Output-heavy reasoning where cheaper tokens matter; Teams that also want first-party image, video and audio APIs.

Is Anthropic or xAI cheaper?

Anthropic: $0.10–$10 in, $0.50–$50 out per 1M. xAI: $2 in, $6 out (Grok 4.7); 2x past 200K. The cheaper choice depends on the model and workload.

Which has more context, Anthropic or xAI?

Anthropic: 1M; Haiku 5.5 costs more past 100K. xAI: 500K (4.7), 1M (4.20, 4.3).

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If your agents run past 200K tokens, compare both against Subconscious. Our inference stack treats a long-horizon trace as the primary workload, so speed, cost, and accuracy hold up deep into the trace.