As of: 2026-11-13 13:49 CET.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/
Canonical page: https://postcutoff.com/m/pi-0/

# π0 (pi-zero)

Physical Intelligence, π (pi) family. Status: legacy. Type: robotics model. Released: 2024-10-31.

## How to call it

| Provider | Model id | Endpoint | Docs |
|---|---|---|---|
| GitHub (openpi, JAX + PyTorch) | `gs://openpi-assets/checkpoints/pi0_base` |  | https://github.com/Physical-Intelligence/openpi |
| Hugging Face (LeRobot port) | `lerobot/pi0_base` |  | https://huggingface.co/docs/lerobot/pi0 https://huggingface.co/lerobot/pi0_base |

## Pricing

- Price not published.
- Last checked: 2026-09-29

## Specs

- Input: text, image
- Output: action
- Context window: not published
- Max output: not published
- Open weights: yes
- Licence: apache-2.0 (openpi code); weights built on PaliGemma, Gemma terms apply

## Where it stands

- Newer robotics models in the registry since its release: 31. The 5 newest:
  - Praxis-1 (2026-09-30) https://postcutoff.com/m/praxis-1/
  - Helix 2.5 (2026-09-17) https://postcutoff.com/m/figure-helix-2-5/
  - UnifoLM-WLA-1.0 (2026-09-10) https://postcutoff.com/m/unifolm-wla-1-0/
  - Skild S1 (Skild Brain) (2026-08-25) https://postcutoff.com/m/skild-s1/
  - Generalist GEN-1.5 (2026-08-19) https://postcutoff.com/m/generalist-gen-1-5/
- After it from Physical Intelligence: π0-FAST (2025-01-16) https://postcutoff.com/m/pi-0-fast/
- Weights are public. Licence: apache-2.0; weights built on PaliGemma, Gemma terms apply. See the licence for commercial terms.

## What stands out

- Flow-matching VLA for dexterous, high-frequency control: PaliGemma VLM plus an action expert that outputs continuous action chunks via flow matching (up to 50 Hz), trained on data from 8 distinct robots; folds laundry, busses tables, assembles boxes. Source: https://www.pi.website/blog/pi0
- Open weights with fine-tuning recipes (found after launch): Open-sourced 2025-02-04 in openpi with base and fine-tuned checkpoints (ALOHA towel/tupperware/pen, DROID) pre-trained on 10k+ hours of robot data; inference needs >8 GB VRAM, LoRA fine-tuning >22.5 GB. Source: https://github.com/Physical-Intelligence/openpi

## Notes

Announced 2024-10-31; weights released 2025-02-04 (openpi). Not the first open VLA (OpenVLA/Octo came earlier) but became the most widely used open generalist robot policy baseline. Superseded by π0.5; still available. Fine-tuned expert checkpoints: pi0_droid, pi0_aloha_towel, pi0_aloha_tupperware, pi0_aloha_pen_uncap.

Physical Intelligence's first generalist robot policy and the base of the open-source openpi stack.

Sources: [π0 blog](https://www.pi.website/blog/pi0), [Open Sourcing π0](https://www.pi.website/blog/openpi), [openpi](https://github.com/Physical-Intelligence/openpi), [The Robot Report](https://www.therobotreport.com/physical-intelligence-open-sources-pi0-robotics-foundation-model/).

Model page: https://postcutoff.com/m/pi-0/