DeepSeek-V4.1-Flash vs Grok 4 Fast
DeepSeek-V4.1-Flash leads the LLM Stats Score 51.8 to 31.7. Grok 4 Fast is 1.2x cheaper per token.
DeepSeek · xAI · Updated for 2026
Which is better?
DeepSeek-V4.1-Flash leads the overall LLM Stats Score 51.8 to 31.7, ranking #13 overall.
In the 2 individual benchmarks reported for both models, DeepSeek-V4.1-Flash wins 2; this is a narrower head-to-head signal than the composite indexes.
On price, Grok 4 Fast is roughly 1.2x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Grok 4 Fast also accepts a larger context window (2,000,000 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose DeepSeek-V4.1-Flash
- overall performance matters — it scores 51.8 and ranks #13 on LLM Stats
- your work emphasizes reasoning and coding — it leads those capability indexes
- you value its reported benchmark strengths — it wins 2 of 2 exact shared results
- you want the most recent training data — it shipped Sep 2026
- you need open weights you can self-host or fine-tune
Choose Grok 4 Fast
- cost matters — it's about 1.2x cheaper per token
- you process long inputs — it offers a 2,000,000 token context window
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
20 reported for DeepSeek-V4.1-Flash · 7 for Grok 4 Fast
DeepSeek-V4.1-Flash outperforms in 2 benchmarks (GPQA, Humanity's Last Exam), while Grok 4 Fast is better at 0 benchmarks.
DeepSeek-V4.1-Flash significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, DeepSeek-V4.1-Flash ($0.22/1M tokens) is 1.1x more expensive than Grok 4 Fast ($0.20/1M tokens).
For output processing, DeepSeek-V4.1-Flash ($0.66/1M tokens) is 1.3x more expensive than Grok 4 Fast ($0.50/1M tokens).
In conclusion, DeepSeek-V4.1-Flash is more expensive than Grok 4 Fast.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Grok 4 Fast accepts 2,000,000 input tokens compared to DeepSeek-V4.1-Flash's 1,040,000 tokens. DeepSeek-V4.1-Flash can generate longer responses up to 393,216 tokens, while Grok 4 Fast is limited to 30,000 tokens.
Input capabilities
Documented input modalities across available providers
Both DeepSeek-V4.1-Flash and Grok 4 Fast support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
DeepSeek-V4.1-Flash
Grok 4 Fast
License
Usage and distribution terms
DeepSeek-V4.1-Flash is licensed under MIT, while Grok 4 Fast uses a proprietary license.
License differences may affect how you can use these models in commercial or open-source projects.
MIT
Open weights
Proprietary
Closed source
Release Timeline
When each model was launched
DeepSeek-V4.1-Flash was released on 2026-09-10, while Grok 4 Fast was released on 2025-08-28.
DeepSeek-V4.1-Flash is 13 months newer than Grok 4 Fast.
Sep 10, 2026
1 weeks ago
1.0yr newerAug 28, 2025
1.1 years ago
Knowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
DeepSeek-V4.1-Flash is available from Fireworks, DeepInfra, DeepSeek, Novita. Grok 4 Fast is available from xAI.
DeepSeek-V4.1-Flash
Grok 4 Fast
Outputs Comparison
Judge for yourself.
Run your own prompts against DeepSeek-V4.1-Flash and Grok 4 Fast side-by-side, then vote on the output you prefer.
FAQ
Common questions about DeepSeek-V4.1-Flash vs Grok 4 Fast.