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Figure 60: Gemma 4 26B-A4B · diagram by Sebastian Raschka · click to zoom
Sparse MoEGoogle 🇺🇸 · April 2, 2026

Gemma 4 (26B-A4B)

Sparse Gemma 4 variant that keeps the local:global attention backbone while swapping dense FFNs for MoE layers.

Key detail

Uses 128 total experts with only 8 routed plus 1 shared expert active per token.

Total params

25B

Active / token

3.8B

Context

256K

Fact sheet

Scale
25.2B total, 3.8B active (15.1% active)
Context window
256,000 tokens
Decoder type
Sparse MoE
Attention
GQA with QK-Norm, unified K/V on global layers, p-RoPE on global layers, and 5:1 sliding-window/global attention
Layer mix
25 sliding-window + 5 global
KV cache / token (bf16)
210 KiB · High
License
Apache License 2.0
Released

Efficiency

Parameters active per token

15%

3.8B of 25B weights run for each token.

KV cache per token (bf16)

210 KiB

Smaller than 22% of models in the atlas. How it’s calculated

AA Intelligence Index v4.3.2

Source

13.1

Scientific
5.7

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