π0.5 (pi-0.5)

Closed weights Physical Intelligence 3.3B parameters April 2025

No estimate

No hardware requirements for this model

The weights for this model have not been published, so it cannot be downloaded or run on your own hardware at any size. It is reachable only through its provider, and no graphics card changes that.

On record

Full specification

Everything on record for this model. Most of it describes how it was trained rather than how it runs — useful context for judging how much work went into it, and how it compares with models built at a different scale.

Origin

Who built this model, where, and when it was published.

Organisation
Physical Intelligence
Organisation type
Industry
Country
United States of America
Published
22 April 2025
Authors
Kevin Black, Noah Brown, James Darpinian, Karan Dhabalia, Danny Driess, Adnan Esmail, Michael Equi, Chelsea Finn, Niccolo Fusai, Manuel Y. Galliker, Dibya Ghosh, Lachy Groom, Karol Hausman, Brian Ichter, Szymon Jakubczak, Tim Jones, Liyiming Ke, Devin LeBlanc, Sergey Levine, Adrian Li-Bell, Mohith Mothukuri, Suraj Nair, Karl Pertsch, Allen Z. Ren, Lucy Xiaoyang Shi, Laura Smith, Jost Tobias Spring…

What it does

The problem areas the model was built for. A model can carry several of each.

Domain
Robotics, Vision
Task
Robotic manipulation
Base model
PaliGemma

Size

How large the model is and how much data it was trained on. Parameters are the figure that decides whether it fits on a given graphics card.

Parameters
3.3B

Fig. 3: Model overview pre-training: - PaliGemma (3B): SigLIP (400M) + Gemma (2.6B) - FAST tokenizer post-training: - pretrained VLM (3B) - action expert (300M) inference: same as post-training this is in line with π0's 3.3B parameters

Training data
tokens

Availability

Whether you can obtain the model and run it on your own hardware, which is what decides if any of the graphics-card figures on this page apply.

Weights
Closed — provider access only
Model access
Unreleased

How it is classified

Labels the source dataset applies when tracking notable models, and how confident it is in the entry.

Record confidence
Confident
Citations
337

Sources

Where this record came from and when it was last checked.

Reference
$π_{0.5}$: a Vision-Language-Action Model with Open-World Generalization
Last updated
11 February 2026

What the numbers mean

Where it came from

π0.5 (pi-0.5) was published by Physical Intelligence, in United States of America, in April 2025. The organisation is categorised as industry.

It works in Robotics, Vision, and is recorded as doing robotic manipulation.

It builds on PaliGemma, which is why it shares that model's general shape and size.

Because the weights are not available, none of the hardware figures elsewhere on this site apply to it.

Answers

π0.5 (pi-0.5) — common questions

01

Is π0.5 (pi-0.5) open source?

No. π0.5 (pi-0.5) has not had its weights published, so it exists only as a service controlled by its owner.

02

How many parameters does π0.5 (pi-0.5) have?

π0.5 (pi-0.5) has 3.3B parameters. Fig. 3: Model overview pre-training: - PaliGemma (3B): SigLIP (400M) + Gemma (2.6B) - FAST tokenizer post-training: - pretrained VLM (3B) - action expert (300M) inference: same as post-training this is in line with π0's 3.3B parameters. That figure is the total, and it is what decides how much memory the model needs — roughly half a gigabyte per billion at the compression most people use.

03

Who created π0.5 (pi-0.5)?

π0.5 (pi-0.5) was published by Physical Intelligence, based in United States of America, categorised as industry.

04

When was π0.5 (pi-0.5) released?

π0.5 (pi-0.5) was published in April 2025.

05

What is π0.5 (pi-0.5) used for?

π0.5 (pi-0.5) works in Robotics, Vision, and is recorded as handling robotic manipulation. Models frequently carry more than one of each, and the tags describe purpose rather than capability limits.

06

What GPU do I need to run π0.5 (pi-0.5)?

None. π0.5 (pi-0.5) is a closed model — its weights were never published, so it cannot be downloaded or run on your own hardware at any price. It is reachable only through its provider.

Source

Original publication

Record last updated 11 February 2026

The other direction

Looking at it from the other side?

This page starts from the model. If you already own a card and want to know everything it will run, start from the hardware instead.