Active Parameters
15B
Context Length
256K
Modality
Text
Architecture
Mixture of Experts (MoE)
License
MIT
Release Date
10 Dec 2025
Knowledge Cutoff
Dec 2024
VRAM requirements for different quantization methods and context sizes
1,024 tokens
Consumer
2x RTX 4090
24GB VRAM
Datacenter
1x NVIDIA A100
80GB VRAM
Apple Silicon
1x Apple M3 Max
128GB VRAM
256,000 tokens
Consumer
4x RTX 4090
24GB VRAM
Datacenter
2x NVIDIA A100
80GB VRAM
Apple Silicon
1x Apple M3 Max
128GB VRAM
Rank
#96
| Benchmark | Score | Rank |
|---|---|---|
Graduate-Level QA | 0.837 | 15 |
Web Development | 1330 | 72 |
General Text | 1393 | 88 |
Overall Rank
#96
Coding Rank
#75
The Xiaomi MiMo V2 Flash is a high-efficiency Mixture-of-Experts (MoE) language model engineered for advanced reasoning, software engineering, and autonomous agentic workflows. Built upon a sparse architecture, the model incorporates a total of 309 billion parameters while activating only 15 billion parameters per forward pass, effectively balancing the modeling capacity of a large-scale system with the inference speed and operational efficiency of a significantly smaller dense model. Its development focus centers on high-throughput performance, achieving high decoding speeds through structural innovations designed to alleviate the computational and memory bottlenecks typically associated with large-scale transformer models.
Technically, MiMo V2 Flash introduces a hybrid attention mechanism that interleaves Sliding Window Attention (SWA) and Global Attention (GA) in a 5:1 ratio across its transformer blocks. This configuration utilizes an aggressive 128-token sliding window, which reduces KV-cache memory requirements by nearly six-fold compared to standard global attention, while a learnable attention sink bias ensures stable long-context performance. Furthermore, the model features a native Multi-Token Prediction (MTP) module consisting of lightweight 0.33 billion parameter dense feed-forward blocks. This MTP architecture facilitates parallel token generation and verification, resulting in a reported increase in decoding throughput by 2.0 to 2.6 times relative to conventional autoregressive generation methods.
Pre-trained on a massive 27 trillion token corpus using FP8 mixed precision, MiMo V2 Flash supports a native sequence length of 32,000 tokens and is capable of handling context windows up to 256,000 tokens. The post-training phase utilizes a novel Multi-Teacher On-Policy Distillation (MOPD) paradigm and large-scale reinforcement learning, specifically targeting complex reasoning and multi-step tool use. This specialized training enables the model to perform reliably in demanding technical scenarios, such as document analysis and extended agentic interactions, making it a resource-optimized solution for researchers and developers requiring state-of-the-art performance in open-weight formats.
Attention
Attention Structure
Multi-Head Attention
Attention Heads
64
Key-Value Heads
8
Attention Head Dimension
128
Position Embedding
Absolute Position Embedding
RoPE Theta
640,000
Sliding Window Attention
No
Sliding Window Size
-
Sliding Window Ratio
-
Linear Attention
-
Linear Attention Ratio
-
Normalization
RMS Normalization
Activation Function
SwigLU
Dimensions
Hidden Dimension Size
4,096
Number of Layers
48
FFN Intermediate Size (Dense)
11,008
Multi-Token Prediction Heads
1
Tokenizer
Vocabulary Size
151,680
Mixture of Experts
Total Expert Parameters
309.0B
Number of Experts
256
Active Experts
8
Shared Experts
-
FFN Intermediate Size (per Expert)
-
Dense Layers Before MoE
-
MiMo-V2-Flash is a Mixture-of-Experts (MoE) model with hybrid attention architecture designed for high-speed reasoning and agentic workflows. It features Multi-Token Prediction (MTP) to achieve state-of-the-art performance while significantly reducing inference costs. The model is optimized for long-context modeling and efficient inference.
APX AI
Online