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ERNIE-4.5-21B-A3B-Base

Active Parameters

21B

Context Length

131.072K

Modality

Text

Architecture

Mixture of Experts (MoE)

License

Apache 2.0

Release Date

30 Jun 2025

Knowledge Cutoff

-

Technical Specifications

Total Expert Parameters

3.0B

Number of Experts

64

Active Experts

6

Attention Structure

Grouped-Query Attention

Hidden Dimension Size

-

Number of Layers

28

Attention Heads

20

Key-Value Heads

4

Activation Function

-

Normalization

-

Position Embedding

Absolute Position Embedding

System Requirements

VRAM requirements for different quantization methods and context sizes

ERNIE-4.5-21B-A3B-Base

The ERNIE-4.5-21B-A3B-Base model is a constituent of Baidu's ERNIE 4.5 family, designed as a powerful, text-focused Mixture-of-Experts (MoE) base model. While the broader ERNIE 4.5 family undergoes joint training on both textual and visual modalities, this specific variant has its text-related parameters extracted, optimizing it for natural language tasks. Its architectural design leverages a heterogeneous MoE structure, which incorporates modality-isolated routing, router orthogonal loss, and multimodal token-balanced loss to ensure effective representation and learning across modalities, even if this variant is primarily for text completion.

This model is engineered for computational efficiency and high performance, supporting a long context length of up to 131,072 tokens. Its MoE architecture distributes the total 21 billion parameters across 64 experts, with 6 active experts per token during generation steps. This design facilitates efficient resource utilization and scalable deployment, benefiting from techniques such as intra-node expert parallelism, memory-efficient pipeline scheduling, and FP8 mixed-precision training. The emphasis on efficiency extends to inference, with strategies like multi-expert parallel collaboration and convolutional code quantization enabling 4-bit/2-bit lossless quantization.

The primary use case for the ERNIE-4.5-21B-A3B-Base model is general-purpose language understanding and generation tasks. It is optimized for Chinese and English text processing, making it suitable for applications requiring robust text completion and comprehension. The model's foundation on the PaddlePaddle deep learning framework further ensures high-performance inference and simplified deployment across various hardware platforms.

About ERNIE 4.5

The Baidu ERNIE 4.5 family consists of ten large-scale multimodal models. They utilize a heterogeneous Mixture-of-Experts (MoE) architecture, which enables parameter sharing across modalities while also employing dedicated parameters for specific modalities, supporting efficient language and multimodal processing.


Other ERNIE 4.5 Models

Evaluation Benchmarks

Ranking is for Local LLMs.

No evaluation benchmarks for ERNIE-4.5-21B-A3B-Base available.

Rankings

Overall Rank

-

Coding Rank

-

GPU Requirements

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Context Size: 1,024 tokens

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