API cost decision in 10 seconds

NewGrok 4.3 vs Claude Opus 4.6 (Fast)

Pick Grok 4.3 when budget is the priority.

Pricing data updated: 2026-05-26T11:08:00Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Grok 4.3 when budget is the priority.

On the standard 1M input plus 500K output workload, Grok 4.3 is estimated at $2.5 vs $105 for Claude Opus 4.6 (Fast), saving $102.5 (97.6% lower).

Cost-first pickGrok 4.3

Context-first pickBoth models

Sample savings$102.597.6%

10x traffic gap$1025

The reported context window is tied, so cost and provider fit carry more weight. At 10x that traffic, the same price gap is about $1025. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Grok 4.3 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	Grok 4.3	Claude Opus 4.6 (Fast)
Input-heavy / RAG	5M input + 500K output	Grok 4.3	$7.5	$225
Balanced workload	1M input + 1M output	Grok 4.3	$3.75	$180
Output-heavy chatbot	1M input + 5M output	Grok 4.3	$13.75	$780

Cheaper input Grok 4.3 $1.25 vs $30 / 1M

Grok 4.3 is $28.75 cheaper per 1M input tokens (95.8% lower; 24x difference).

Cheaper output Grok 4.3 $2.5 vs $150 / 1M

Grok 4.3 is $147.5 cheaper per 1M output tokens (98.3% lower; 60x difference).

Larger context Tie 1M vs 1M

Both models report the same context window at 1M tokens.

Sample workload Grok 4.3 $2.5 vs $105

Grok 4.3 is $102.5 cheaper on the standard workload (97.6% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.

Monthly input tokens Monthly output tokens

Grok 4.3 Calculating… Estimated API cost

Claude Opus 4.6 (Fast) Calculating… Estimated API cost

Cheaper for this workload Calculating… Difference: calculating…

This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.

Quick Decision

Verdict

Grok 4.3 has the lower input price; Grok 4.3 has the lower output price; both models report the same context window. For the 1M input plus 500K output sample, Grok 4.3 is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $2.5 for Grok 4.3 and $105 for Claude Opus 4.6 (Fast).

Best Fit

Choose Grok 4.3 when you care most about lower input-token price, and lower output-token price.

Choose Claude Opus 4.6 (Fast) when its provider, model quality, latency, or availability is more important than the numeric price/context winner.

Decision Notes

On the standard 1M input plus 500K output workload, Grok 4.3 is estimated at $2.5 vs $105 for Claude Opus 4.6 (Fast), saving $102.5 (97.6% lower).
Grok 4.3 is $102.5 cheaper on the standard workload (97.6% lower).
Grok 4.3 is $28.75 cheaper per 1M input tokens (95.8% lower; 24x difference).
Grok 4.3 is $147.5 cheaper per 1M output tokens (98.3% lower; 60x difference).
Both models report the same context window at 1M tokens.

Head-to-Head Specs

Feature	NewGrok 4.3 (xAI)	Claude Opus 4.6 (Fast) (Anthropic)
Input Price prompt tokens per 1M	$1.25	$30
Completion Price per 1M tokens	$2.5	$150
Sample Workload Cost 1M input + 500K output	$2.5	$105
Context Window	1M	1M
Release Date	2026-04-30	2026-04-07

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Grok 4.3	On the standard 1M input plus 500K output workload, Grok 4.3 is estimated at $2.5 vs $105 for Claude Opus 4.6 (Fast), saving $102.5 (97.6% lower).
High-volume input processing	Grok 4.3	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	Grok 4.3	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Tie	A larger context window leaves more room for retrieved passages, conversation history, or source files.

Related Alternatives

Same-provider lower-cost swaps

Grok Build 0.1 can replace Grok 4.3 when lower sample workload cost matters most: $2.
Claude 3 Haiku can replace Claude Opus 4.6 (Fast) when lower sample workload cost matters most: $0.88.
Claude 3.5 Haiku can replace Claude Opus 4.6 (Fast) when lower sample workload cost matters most: $2.8.
Anthropic Claude Haiku Latest can replace Claude Opus 4.6 (Fast) when lower sample workload cost matters most: $3.5.

Larger context near this budget

Llama 4 Scout offers 10M context with $0.23 sample workload cost.
Grok 4.20 Multi-Agent offers 2M context with $5 sample workload cost.
Grok 4.20 offers 2M context with $2.5 sample workload cost.
OpenAI GPT Latest offers 1.05M context with $20 sample workload cost.

Popular competitors

No popular competitor is currently available.

Cheaper alternatives

Review low-cost models sorted by a standard 1M input plus 500K output workload.

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Larger context alternatives

Find models with larger context windows for RAG, long documents, and codebase review.

Open largest context models

Provider catalogs

Compare models within provider hubs before choosing a final API vendor.

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xAI catalog

Review all tracked xAI models before deciding whether this matchup is the right shortlist.

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Anthropic catalog

Check other Anthropic models with comparable pricing, context, or release timing.

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Grok 4.3

Grok 4.3 is a reasoning model from xAI. It accepts text and image inputs with text output, and is suited for agentic workflows, instruction-following tasks, and applications requiring high factual...

Claude Opus 4.6 (Fast)

Fast-mode variant of [Opus 4.6](/anthropic/claude-opus-4.6) - identical capabilities with higher output speed at premium 6x pricing. Learn more in Anthropic's docs: https://platform.claude.com/docs/en/build-with-claude/fast-mode