---
license: gemma
base_model: google/gemma-3-1b-pt
tags:
- jax
- orbax
- tensorstore
- gemma
- conversion
---

# Gemma 3 1B PT – Orbax/TensorStore (OCDBT)

This repository contains the **Orbax/TensorStore (OCDBT)** checkpoint converted from
`google/gemma-3-1b-pt` Hugging Face safetensors. The conversion stacks transformer
layer weights along the depth axis for efficient JAX/Orbax loading.

Conversion script can be found at on GitHub: https://github.com/dominik3141/hf-to-orbax

## What’s included

- Orbax/TensorStore checkpoint files (OCDBT)
- `LICENSE` and `NOTICE` per Gemma Terms of Use

## Conversion details

- Source: `google/gemma-3-1b-pt`
- Format change only: **no weight changes** beyond layout/format
- Layer weights use the same HF key with the numeric layer index removed and are stacked on axis 0.
  Example: `model.layers.12.self_attn.q_proj.weight` → `model.layers.self_attn.q_proj.weight`

## Loading example (JAX/Orbax)

```python
from huggingface_hub import snapshot_download
import orbax.checkpoint as ocp

path = snapshot_download("dffarr/gemma-3-1b-pt-orbax")
ckpt = ocp.StandardCheckpointer().restore(path)

# Example access
embed_tokens = ckpt["model.embed_tokens.weight"]
q_proj = ckpt["model.layers.self_attn.q_proj.weight"]  # stacked: [num_layers, ...]
```

## License & Use

This repository is provided under the **Gemma Terms of Use**. Please read `LICENSE`
and comply with the **Gemma Prohibited Use Policy**:
https://ai.google.dev/gemma/terms

## Conversion script

The conversion script used to generate this checkpoint is included as `convert.py`.