What is the difference between Grok 4 Fast (free) and Qwen3.5 397B A17B?

Grok 4 Fast (free) is developed by xAI while Qwen3.5 397B A17B is developed by Qwen. Grok 4 Fast (free) has a 2.0M token context window vs Qwen3.5 397B A17B's 262K. You can compare their actual outputs across 34 challenges on Rival to see how they differ in practice.

Which is better, Grok 4 Fast (free) or Qwen3.5 397B A17B?

It depends on your use case. Grok 4 Fast (free) and Qwen3.5 397B A17B each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 34 challenges so you can judge which fits your needs best.

How much does Grok 4 Fast (free) cost compared to Qwen3.5 397B A17B?

Grok 4 Fast (free) costs $0/M input tokens and Qwen3.5 397B A17B costs $0.6/M input tokens. Grok 4 Fast (free) is $0.60/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Grok 4 Fast (free) and Qwen3.5 397B A17B on Rival?

This page shows a side-by-side comparison of Grok 4 Fast (free) and Qwen3.5 397B A17B across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

What is the difference between Grok 4 Fast (free) and Qwen3.5 397B A17B?

Grok 4 Fast (free) is developed by xAI while Qwen3.5 397B A17B is developed by Qwen. Grok 4 Fast (free) has a 2.0M token context window vs Qwen3.5 397B A17B's 262K. You can compare their actual outputs across 34 challenges on Rival to see how they differ in practice.

Which is better, Grok 4 Fast (free) or Qwen3.5 397B A17B?

It depends on your use case. Grok 4 Fast (free) and Qwen3.5 397B A17B each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 34 challenges so you can judge which fits your needs best.

How much does Grok 4 Fast (free) cost compared to Qwen3.5 397B A17B?

Grok 4 Fast (free) costs $0/M input tokens and Qwen3.5 397B A17B costs $0.6/M input tokens. Grok 4 Fast (free) is $0.60/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Grok 4 Fast (free) and Qwen3.5 397B A17B on Rival?

This page shows a side-by-side comparison of Grok 4 Fast (free) and Qwen3.5 397B A17B across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

Grok 4 Fast (free) vs Qwen3.5 397B A17B: Which Is Better?

Updated Feb 2026

Our Verdict

Grok 4 Fast (free)

Qwen3.5 397B A17B

No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.

Too close to call

What do Grok 4 Fast (free) and Qwen3.5 397B A17B say about your brand?

10 models, one question, verbatim receipts.

or peek at a demo: Notion Linear Vercel

API pricing

Cost per 1M tokens

Grok 4 Fast (free)

Input

$0.000

Output

$0.000

Qwen3.5 397B A17B

Input

$0.60

Output

$3.60

Writing DNA

Style Comparison

Similarity

41%

Qwen3.5 397B A17B uses 22.8x more emoji

Grok 4 Fast (free)

Qwen3.5 397B A17B

65%Vocabulary54%

13wSentence Length14w

0.56Hedging0.39

1.4Bold6.9

2.5Lists4.2

0.00Emoji0.23

1.58Headings0.93

0.28Transitions0.17

Based on 14 + 23 text responses

Research

What we learned reading every model

FAQ

Common questions

Keep exploring

More comparisons

Grok 4 Fast (free) vs Ox AlphaNew provider

Grok 4 Fast (free) vs MiniMax M3New provider

Grok 4 Fast (free) vs GPT-5New provider

Updated Feb 2026

Our Verdict

Grok 4 Fast (free)

Qwen3.5 397B A17B

No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.

Too close to call

What do Grok 4 Fast (free) and Qwen3.5 397B A17B say about your brand?

10 models, one question, verbatim receipts.

or peek at a demo: Notion Linear Vercel

API pricing

Cost per 1M tokens

Grok 4 Fast (free)

Input

$0.000

Output

$0.000

Qwen3.5 397B A17B

Input

$0.60

Output

$3.60

Writing DNA

Style Comparison

Similarity

41%

Qwen3.5 397B A17B uses 22.8x more emoji

Grok 4 Fast (free)

Qwen3.5 397B A17B

65%Vocabulary54%

13wSentence Length14w

0.56Hedging0.39

1.4Bold6.9

2.5Lists4.2

0.00Emoji0.23

1.58Headings0.93

0.28Transitions0.17

Based on 14 + 23 text responses

Research

What we learned reading every model

FAQ

Common questions

Keep exploring

More comparisons

Grok 4 Fast (free) vs Ox AlphaNew provider

Grok 4 Fast (free) vs MiniMax M3New provider

Grok 4 Fast (free) vs GPT-5New provider