API cost decision in 10 seconds

🔥Gemini 3 Flash Preview vs 🔥Grok 4.1 Fast

Pick Grok 4.1 Fast when budget and context both matter.

Pricing data updated:  Prices normalized to USD per 1M tokens Sample workload: 1M input + 500K output

Budget verdict

Pick Grok 4.1 Fast when budget and context both matter.

On the standard 1M input plus 500K output workload, Grok 4.1 Fast is estimated at $0.45 vs $2 for Gemini 3 Flash Preview, saving $1.55 (77.5% lower).

Cost-first pickGrok 4.1 Fast
Context-first pickGrok 4.1 Fast
Sample savings$1.5577.5%
10x traffic gap$15.5

Grok 4.1 Fast is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $15.5. Use the calculator below to replace the sample workload with your own token volume.

Cheaper input Grok 4.1 Fast $0.5 vs $0.2 / 1M

Grok 4.1 Fast is $0.3 cheaper per 1M input tokens (60% lower; 2.5x difference).

Cheaper output Grok 4.1 Fast $3 vs $0.5 / 1M

Grok 4.1 Fast is $2.5 cheaper per 1M output tokens (83.3% lower; 6x difference).

Larger context Grok 4.1 Fast 1.05M vs 2M

Grok 4.1 Fast has 951.42K more context (1.91x larger).

Sample workload Grok 4.1 Fast $2 vs $0.45

Grok 4.1 Fast is $1.55 cheaper on the standard workload (77.5% lower).

Estimate your workload cost

Your Workload Cost

Prices are normalized to USD per 1M tokens.
Gemini 3 Flash Preview Calculating… Estimated API cost
Grok 4.1 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 4.1 Fast has the lower input price; Grok 4.1 Fast has the lower output price; Grok 4.1 Fast offers the larger context window. For the 1M input plus 500K output sample, Grok 4.1 Fast is cheaper for the standard workload.

For a 1M input token plus 500K output token workload, the estimated API cost is $2 for Gemini 3 Flash Preview and $0.45 for Grok 4.1 Fast.

Best Fit

Choose Gemini 3 Flash Preview when its provider, model quality, latency, or availability is more important than the numeric price/context winner.

Choose Grok 4.1 Fast when you care most about lower input-token price, lower output-token price, and larger context window.

Decision Notes
  • On the standard 1M input plus 500K output workload, Grok 4.1 Fast is estimated at $0.45 vs $2 for Gemini 3 Flash Preview, saving $1.55 (77.5% lower).
  • Grok 4.1 Fast is $1.55 cheaper on the standard workload (77.5% lower).
  • Grok 4.1 Fast is $0.3 cheaper per 1M input tokens (60% lower; 2.5x difference).
  • Grok 4.1 Fast is $2.5 cheaper per 1M output tokens (83.3% lower; 6x difference).
  • Grok 4.1 Fast has 951.42K more context (1.91x larger).
Head-to-Head Specs
Feature🔥Gemini 3 Flash Preview
(Google)
🔥Grok 4.1 Fast
(xAI)
Input Price
prompt tokens per 1M
$0.5$0.2
Completion Price
per 1M tokens
$3$0.5
Sample Workload Cost
1M input + 500K output
$2$0.45
Context Window1.05M2M
Release Date2025-12-172025-11-19
Popularity Rank
current rank
#6#18

Use-Case Decision Matrix

Use caseBetter pickWhy
Budget-constrained productionGrok 4.1 FastOn the standard 1M input plus 500K output workload, Grok 4.1 Fast is estimated at $0.45 vs $2 for Gemini 3 Flash Preview, saving $1.55 (77.5% lower).
High-volume input processingGrok 4.1 FastLower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill.
Long responses and chatbotsGrok 4.1 FastLower output-token price matters most when assistants generate many completion tokens.
RAG or long-document workGrok 4.1 FastA larger context window leaves more room for retrieved passages, conversation history, or source files.

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