# Gemma 3 (270M)

> Tiny Gemma 3 variant that preserves the family's local-global attention recipe at a toy scale.

| Property | Value |
| --- | --- |
| Lab | Google (United States) |
| Released | 2025-08-14 |
| Decoder type | Dense |
| Family | Dense |
| Scale | 270M parameters |
| Context window | 128,000 tokens |
| Attention | Multi-query attention with QK-Norm and 5:1 sliding-window/global attention |
| Layer mix | 15 sliding-window + 3 global |
| KV cache / token (bf16) | 18 KiB (Very low) |
| License | Gemma Terms of Use + Gemma Prohibited Use Policy |

**Key detail:** Keeps the Gemma 3 stack shape while shrinking down to 4 attention heads, a single KV head, and the same 262k vocabulary.

## Architecture concepts

- [QK-Norm (QK-Norm)](https://llm-atlas-7or.pages.dev/concepts/qk-norm.md): RMSNorm applied to queries and keys before attention to keep logits well-behaved.
- [Sliding Window Attention (SWA)](https://llm-atlas-7or.pages.dev/concepts/swa.md): Some layers only attend to a local window of recent tokens instead of the whole context.

## Benchmark (Artificial Analysis Intelligence Index)

- AA Intelligence Index v4.3.2: total 5.1 (Scientific 1.8)

## Links

- Architecture diagram: https://sebastianraschka.com/llm-architecture-gallery/images/architectures/gemma-3-270m.webp
- View in article: https://magazine.sebastianraschka.com/p/the-big-llm-architecture-comparison#%C2%A74-mistral-small-31
- From scratch: https://github.com/rasbt/LLMs-from-scratch/tree/main/ch05/12_gemma3
- config.json: https://huggingface.co/google/gemma-3-270m/blob/main/config.json
- License: https://ai.google.dev/gemma/prohibited_use_policy
- Tech report: https://arxiv.org/pdf/2503.19786
- Source card (source of truth): https://sebastianraschka.com/llm-architecture-gallery/#card-gemma-3-270m
- Web page: https://llm-atlas-7or.pages.dev/models/gemma-3-270m/
- JSON: https://llm-atlas-7or.pages.dev/api/models/gemma-3-270m.json

_Data from Sebastian Raschka's LLM Architecture Gallery (https://sebastianraschka.com/llm-architecture-gallery/). Synced 2026-11-04._