Grok 4 Fast vs Particle-1
Grok 4 Fast and Particle-1 are closely matched at 30.9 and 31.9 on the LLM Stats Score. Grok 4 Fast is 1.6x cheaper per token.
xAI · Particle AI · Updated for 2026
Which is better?
Grok 4 Fast and Particle-1 are closely matched on the overall LLM Stats Score at 30.9 and 31.9.
In the 1 individual benchmarks reported for both models, Particle-1 wins 1; this is a narrower head-to-head signal than the composite indexes.
On price, Grok 4 Fast is roughly 1.6x 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 Grok 4 Fast
- cost matters — it's about 1.6x cheaper per token
- you process long inputs — it offers a 2,000,000 token context window
Choose Particle-1
- you value its reported benchmark strengths — it wins 1 of 1 exact shared results
- you want the most recent training data — it shipped Oct 2026
At a glance
The differences that matter most.
Individual benchmarks
7 reported for Grok 4 Fast · 3 for Particle-1
Grok 4 Fast outperforms in 0 benchmarks, while Particle-1 is better at 1 benchmark (GPQA).
Particle-1 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, Grok 4 Fast ($0.20/1M tokens) is 1.3x cheaper than Particle-1 ($0.25/1M tokens).
For output processing, Grok 4 Fast ($0.50/1M tokens) is 2.0x cheaper than Particle-1 ($1.00/1M tokens).
In conclusion, Particle-1 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 Particle-1's 1,048,576 tokens. Particle-1 can generate longer responses up to 131,072 tokens, while Grok 4 Fast is limited to 30,000 tokens.
Input capabilities
Documented input modalities across available providers
Both Grok 4 Fast and Particle-1 support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Grok 4 Fast
Particle-1
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Grok 4 Fast was released on 2025-08-28, while Particle-1 was released on 2026-10-28.
Particle-1 is 14 months newer than Grok 4 Fast.
Aug 28, 2025
1.2 years ago
Oct 28, 2026
-1 days ago
1.2yr newerKnowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
Grok 4 Fast is available from xAI. Particle-1 is available from Particle AI.
Grok 4 Fast
Particle-1
Outputs Comparison
Judge for yourself.
Run your own prompts against Grok 4 Fast and Particle-1 side-by-side, then vote on the output you prefer.
FAQ
Common questions about Grok 4 Fast vs Particle-1.