API cost decision in 10 seconds

NewGrok 4.3 vs Kimi K2 0905

Pick Kimi K2 0905 for lower cost; pick Grok 4.3 only if the larger context window matters more.

Page updated: 2026-05-26T15:08:08Z Data confirmed: 2026-05-26T19:08:13Z Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Kimi K2 0905 for lower cost; pick Grok 4.3 only if the larger context window matters more.

On the standard 1M input plus 500K output workload, Kimi K2 0905 is estimated at $1.85 vs $2.5 for Grok 4.3, saving $0.65 (26% lower).

Cost-first pickKimi K2 0905

Context-first pickGrok 4.3

Sample savings$0.6526%

10x traffic gap$6.5

Grok 4.3 has more context, but Kimi K2 0905 saves $0.65 on the standard workload. At 10x that traffic, the same price gap is about $6.5. Use the calculator below to replace the sample workload with your own token volume.

Cost sensitivity

Workload Sensitivity

Same prices, different token mixes.

Kimi K2 0905 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.

Workload shape	Token mix	Better pick	Grok 4.3	Kimi K2 0905
Input-heavy / RAG	5M input + 500K output	Kimi K2 0905	$7.5	$4.25
Balanced workload	1M input + 1M output	Kimi K2 0905	$3.75	$3.1
Output-heavy chatbot	1M input + 5M output	Kimi K2 0905	$13.75	$13.1

Cheaper input Kimi K2 0905 $1.25 vs $0.6 / 1M

Kimi K2 0905 is $0.65 cheaper per 1M input tokens (52% lower; 2.08x difference).

Cheaper output Tie $2.5 vs $2.5 / 1M

Both models report the same output price at $2.5 per 1M tokens.

Larger context Grok 4.3 1M vs 262.14K

Grok 4.3 has 737.86K more context (3.81x larger).

Sample workload Kimi K2 0905 $2.5 vs $1.85

Kimi K2 0905 is $0.65 cheaper on the standard workload (26% 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

Kimi K2 0905 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

Kimi K2 0905 has the lower input price; both models tie on output price; Grok 4.3 offers the larger context window. For the 1M input plus 500K output sample, Kimi K2 0905 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 $1.85 for Kimi K2 0905.

Best Fit

Choose Grok 4.3 when you care most about larger context window.

Choose Kimi K2 0905 when you care most about lower input-token price.

Decision Notes

On the standard 1M input plus 500K output workload, Kimi K2 0905 is estimated at $1.85 vs $2.5 for Grok 4.3, saving $0.65 (26% lower).
Kimi K2 0905 is $0.65 cheaper on the standard workload (26% lower).
Kimi K2 0905 is $0.65 cheaper per 1M input tokens (52% lower; 2.08x difference).
Both models report the same output price at $2.5 per 1M tokens.
Grok 4.3 has 737.86K more context (3.81x larger).

Head-to-Head Specs

Feature	NewGrok 4.3 (xAI)	Kimi K2 0905 (MoonshotAI)
Input Price prompt tokens per 1M	$1.25	$0.6
Completion Price per 1M tokens	$2.5	$2.5
Sample Workload Cost 1M input + 500K output	$2.5	$1.85
Context Window	1M	262.14K
Release Date	2026-04-30	2025-09-04
Popularity	#50	#70

Use-Case Decision Matrix

Use case	Better pick	Why
Budget-constrained production	Kimi K2 0905	On the standard 1M input plus 500K output workload, Kimi K2 0905 is estimated at $1.85 vs $2.5 for Grok 4.3, saving $0.65 (26% lower).
High-volume input processing	Kimi K2 0905	Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbots	Tie	Lower output-token price matters most when assistants generate many completion tokens.
RAG or long-document work	Grok 4.3	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.
Kimi K2.5 can replace Kimi K2 0905 when lower sample workload cost matters most: $1.35.
Kimi K2 0711 can replace Kimi K2 0905 when lower sample workload cost matters most: $1.72.

Larger context near this budget

Llama 4 Scout offers 10M context with $0.23 sample workload cost.
Grok 4.20 offers 2M context with $2.5 sample workload cost.
Owl Alpha offers 1.05M context with $0 sample workload cost.
DeepSeek V4 Flash offers 1.05M context with $0.2 sample workload cost.

Popular competitors

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Hy3 preview · Tencent · #2
Claude Opus 4.7 · Anthropic · #3
Claude Sonnet 4.6 · Anthropic · #4

Cheaper alternatives

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Larger context alternatives

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Provider catalogs

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xAI catalog

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MoonshotAI catalog

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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...

Kimi K2 0905

Kimi K2 0905 is the September update of [Kimi K2 0711](moonshotai/kimi-k2). It is a large-scale Mixture-of-Experts (MoE) language model developed by Moonshot AI, featuring 1 trillion total parameters with 32...