What is the difference between Grok 4 Fast (free) and Qwen3.5 Plus 2026-02-15?

Grok 4 Fast (free) is developed by xAI while Qwen3.5 Plus 2026-02-15 is developed by Qwen. Grok 4 Fast (free) has a 2.0M token context window vs Qwen3.5 Plus 2026-02-15's 1.0M. 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 Plus 2026-02-15?

It depends on your use case. Grok 4 Fast (free) and Qwen3.5 Plus 2026-02-15 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 Plus 2026-02-15?

Grok 4 Fast (free) costs $0/M input tokens and Qwen3.5 Plus 2026-02-15 costs $0.4/M input tokens. Grok 4 Fast (free) is $0.40/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 Plus 2026-02-15 on Rival?

This page shows a side-by-side comparison of Grok 4 Fast (free) and Qwen3.5 Plus 2026-02-15 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 Plus 2026-02-15?

Grok 4 Fast (free) is developed by xAI while Qwen3.5 Plus 2026-02-15 is developed by Qwen. Grok 4 Fast (free) has a 2.0M token context window vs Qwen3.5 Plus 2026-02-15's 1.0M. 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 Plus 2026-02-15?

It depends on your use case. Grok 4 Fast (free) and Qwen3.5 Plus 2026-02-15 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 Plus 2026-02-15?

Grok 4 Fast (free) costs $0/M input tokens and Qwen3.5 Plus 2026-02-15 costs $0.4/M input tokens. Grok 4 Fast (free) is $0.40/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 Plus 2026-02-15 on Rival?

This page shows a side-by-side comparison of Grok 4 Fast (free) and Qwen3.5 Plus 2026-02-15 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 Plus 2026-02-15: Which Is Better?

Updated Feb 2026

Our Verdict

Grok 4 Fast (free)

Qwen3.5 Plus 2026-02-15

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 Plus 2026-02-15 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 Plus 2026-02-15

Input

$0.40

Output

$2.40

Writing DNA

Style Comparison

Similarity

39%

Qwen3.5 Plus 2026-02-15 uses 10.0x more emoji

Grok 4 Fast (free)

Qwen3.5 Plus 2026-02-15

65%Vocabulary54%

13wSentence Length18w

0.56Hedging0.51

1.4Bold5.3

2.5Lists2.9

0.00Emoji0.10

1.58Headings0.75

0.28Transitions0.09

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 Plus 2026-02-15

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 Plus 2026-02-15 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 Plus 2026-02-15

Input

$0.40

Output

$2.40

Writing DNA

Style Comparison

Similarity

39%

Qwen3.5 Plus 2026-02-15 uses 10.0x more emoji

Grok 4 Fast (free)

Qwen3.5 Plus 2026-02-15

65%Vocabulary54%

13wSentence Length18w

0.56Hedging0.51

1.4Bold5.3

2.5Lists2.9

0.00Emoji0.10

1.58Headings0.75

0.28Transitions0.09

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