Claude Haiku 4.5vsGrok 4.1 Fast
Grok 4.1 Fast is the newer model, released after Claude Haiku 4.5.
| Spec | Claude Haiku 4.5 | Grok 4.1 Fast |
|---|---|---|
| Input price | $1/M tokens | — |
| Output price | $5/M tokens | — |
| Context window | 200K tokens | — |
| Weights | Closed | — |
| Free API (OpenRouter) | No | No |
| Released | Oct 2025 | Nov 2025 |
Our Verdict
Grok 4.1 Fast
Claude Haiku 4.5Runner-up
Not enough votes to call it. On the specs, Grok 4.1 Fast has the edge: bigger model tier, newer.
Pick Claude Haiku 4.5 for Image Generation, Web Design. Pick Grok 4.1 Fast for Reasoning.
Too close to call
API pricing
Cost per 1M tokens
Claude Haiku 4.5
Input
$1.00
Output
$5.00
Grok 4.1 Fast
Input
—
Output
—
Where to run it
4 hosts
Grok 4.1 Fast
No hosts listed on OpenRouter.
Per million tokens. Prices and uptime via OpenRouter, checked 8 Sep 2026.
Writing DNA
Style Comparison
Similarity
57%
Grok 4.1 Fast uses 4.8x more emoji
Claude Haiku 4.5
Grok 4.1 Fast
61%Vocabulary69%
47wSentence Length15w
0.64Hedging0.20
5.1Bold4.3
6.3Lists3.6
0.20Emoji0.97
2.46Headings0.90
0.17Transitions0.12
Based on 24 + 28 text responses
Research
What we learned reading every model
FAQ
Common questions
Keep exploring
More comparisons
Claude Haiku 4.5 vs Ox AlphaNew provider
Claude Haiku 4.5 vs MiniMax M3New provider
Claude Haiku 4.5 vs Gemini 2.5 Pro (I/O Edition)New provider
Claude Haiku 4.5 vs Gemini 2.5 Pro Preview 06-05New provider
Grok 4.1 Fast vs Claude 3 OpusCross-provider
Grok 4.1 Fast vs Claude 3 SonnetCross-provider
Grok 4.1 Fast vs Claude Sonnet 3.6 (2022-10-22)Cross-provider
Grok 4.1 Fast vs Claude 3.7 SonnetCross-provider