# Open-source humanoids: what you can actually build

> 24 of the 182 humanoids on record call themselves open source. 15 publish hardware files and software, 3 name a licence, 12 can be ordered, and none of the four on preorder has any autonomy evidence yet.

Published: 2026-09-06
Section: Explainer
Author: Geert Jan van Vlastuin, Editor, humanoid.observer
Canonical: https://humanoid.observer/blog/open-source-humanoids-what-you-can-actually-build/
Licence: editorial text all rights reserved. The underlying data is CC BY 4.0 at https://humanoid.observer/data/.
Cite as: humanoid.observer, https://humanoid.observer/blog/open-source-humanoids-what-you-can-actually-build/, accessed <date>.

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"Open source" on a humanoid spec sheet covers everything from a full set of CAD files, a bill of materials and training code, to a software kit for a body you are not allowed to open. Our database flags 24 of 182 robots as open source. Per each record's note on what is released: 15 publish hardware files and software. 3 publish software or documentation and sell the hardware as a kit. 1 releases an "open-source edition" of a product that stays proprietary. 5 say they are open and give no detail.

## What "open" means on each record

The 15 with both are the ones a lab can reproduce. [Berkeley Humanoid Lite](/robots/berkeley-humanoid-lite/) from [UC Berkeley](/companies/uc-berkeley/) put hardware, firmware, simulation and training code on GitHub in April 2025, with 3D printed cycloidal gearboxes and a bill of materials under $5,000. [ToddlerBot](/robots/toddlerbot/) from [Stanford](/companies/stanford-university/) released hardware, firmware and learning code in February 2025 for a 56 cm, 3.4 kg, 30-DOF machine at about $6,000 in parts. [Fourier N1](/robots/fourier-n1/) published CAD, a bill of materials and software under an open licence in April 2025. [iCub](/robots/iit-icub/) from [IIT](/companies/iit/) has had open designs and software since 2008.

The 3 software-and-kit records are [BRUCE](/robots/bruce/) from [UCLA](/companies/ucla/), open control software with the hardware sold as a kit by Westwood Robotics at an unpublished price, and two [Robotis](/companies/robotis/) machines, [ROBOTIS OP3](/robots/robotis-op3/) and the discontinued [THORMANG3](/robots/thormang3/), which publish software and documentation rather than drawings. Their ancestor [DARwIn-OP](/robots/darwin-op/) released drawings, electronics and code in December 2010.

[Leju Kuavo](/robots/leju-kuavo/) is the one-off: an open-source edition of Kuavo 4.0 came out in December 2024 and the full product is proprietary. The 5 with no detail are [HopeJR](/robots/hugging-face-hopejr/), [Z-Bot](/robots/k-scale-z-bot/), [Tiangong 2.0](/robots/tiangong-2/), [Roboy](/robots/devanthro-roboy/) and [Qinglong](/robots/qinglong/), whose note says only that it was released under the OpenLoong program. [Reachy 2](/robots/pollen-reachy-2/) has no note on the robot record; its price record says fully open-source hardware and software.

Only 3 of the 24 name a licence. iCub says GPL and similar. [InMoov](/robots/inmoov/) releases its files under a Creative Commons non-commercial licence, which matters if you planned to sell what you print. [Poppy Humanoid](/robots/poppy-humanoid/) from [Inria](/companies/inria/) uses Creative Commons and GPL. The other 21 say "open licences" or nothing: find the licence file before you build.

## The 24, in one table

Height, weight and joint count come from the records where they exist: 12 give a height, 10 a weight and 14 a DOF figure. A bill of materials is marked as such.

| Machine | Maker | Open per the record | cm / kg / DOF | Price in data | Status |
|---|---|---|---|---|---|
| [Lingxi X1](/robots/agibot-lingxi-x1/) | AgiBot | Structural design and software framework on GitHub | 130 / 33 / 29 | No fixed price | In stock |
| [Fourier N1](/robots/fourier-n1/) | Fourier | CAD, BOM and software, open licence | 130 / 38 / 23 | $40,000 via distributor | In stock |
| [Kuavo](/robots/leju-kuavo/) | Leju | Open-source edition of Kuavo 4.0; product proprietary | n.a. | No verified price | In stock |
| [Qinglong](/robots/qinglong/) | Humanoid Robots (Shanghai) | OpenLoong program, no detail | 185 / 80 / 43 | None | In stock |
| [Reachy 2](/robots/pollen-reachy-2/) | Pollen Robotics | Hardware and software, per price record | Wheeled base, n.a. | $70,000 to $75,000; $38,000 one arm | Built to order |
| [ROBOTIS OP3](/robots/robotis-op3/) | Robotis | Software and hardware documentation | 51 / 3.5 / 20 | Low five figures, ask Robotis | In stock |
| [Tiangong 1.0](/robots/tiangong/) | X-Humanoid | Design and software, Tiangong Open Source | 163 / 43 / n.a. | None | In stock |
| [Tiangong 2.0](/robots/tiangong-2/) | X-Humanoid | No detail | n.a. | None | In stock |
| [HopeJR](/robots/hugging-face-hopejr/) | Hugging Face | No detail; sold as an arms-and-hands kit | n.a. / n.a. / 66 | $3,000 target | Preorder |
| [K-Bot](/robots/k-scale-k-bot/) | K-Scale Labs | Hardware, firmware and software, open licences | n.a. | Developer pricing, unverified | Preorder |
| [Z-Bot](/robots/k-scale-z-bot/) | K-Scale Labs | No detail | n.a. | $999 | Preorder |
| [Reachy Mini](/robots/reachy-mini/) | Pollen Robotics | Hardware and software | 28 / n.a. / n.a. | $299 Lite, $449 wireless | Preorder |
| [BRUCE](/robots/bruce/) | UCLA | Software; hardware as a kit from Westwood Robotics | n.a. / n.a. / 16 | Kit price not public | Enterprise only |
| [iCub](/robots/iit-icub/) | IIT | Hardware designs and software, GPL and similar | 104 / 33 / 53 | Historically around EUR 250,000 | Enterprise only |
| [Berkeley Humanoid Lite](/robots/berkeley-humanoid-lite/) | UC Berkeley | Hardware and software, open licences | n.a. / n.a. / 22 | BOM under $5,000 | Not for sale |
| [HECTOR](/robots/hector/) | USC | Simulation and designs on GitHub | n.a. | None | Not for sale |
| [HumanPlus](/robots/humanplus/) | Stanford | Code and hardware modifications on a Unitree H1 | n.a. / n.a. / 33 | None | Not for sale |
| [InMoov](/robots/inmoov/) | InMoov | Files, Creative Commons non-commercial | Upper body; 5-DOF hands | Parts $1,500 to $3,000 | Not for sale |
| [NimbRo-OP2X](/robots/nimbro-op2x/) | University of Bonn | CAD and software on GitHub | 135 / n.a. / 18 | None | Not for sale |
| [Poppy Humanoid](/robots/poppy-humanoid/) | Inria | Creative Commons and GPL | 83 / 3.5 / 25 | Kits were several thousand euros | Not for sale |
| [Roboy](/robots/devanthro-roboy/) | Devanthro | No detail | n.a. | None | Not for sale |
| [ToddlerBot](/robots/toddlerbot/) | Stanford | Hardware, firmware and learning code on GitHub | 56 / 3.4 / 30 | BOM about $6,000 | Not for sale |
| [DARwIn-OP](/robots/darwin-op/) | Robotis | Mechanical drawings, electronics and code | 45.5 / 2.9 / 20 | About $12,000 at launch | Discontinued |
| [THORMANG3](/robots/thormang3/) | Robotis | Software and documentation | 137 / 42 / 29 | Not public | Discontinued |

## Half of them come from universities

11 of the 24 come from a university or research institute: Berkeley, UCLA, USC, Stanford twice, Bonn, IIT, Inria, and the Chinese state innovation centres in Shanghai and Beijing behind Qinglong, [Tiangong 1.0](/robots/tiangong/) and Tiangong 2.0. The other 13 come from companies: three from Robotis, two each from [K-Scale Labs](/companies/k-scale-labs/) and [Pollen Robotics](/companies/pollen-robotics/), one each from [AgiBot](/companies/agibot/), [Fourier](/companies/fourier/), [Hugging Face](/companies/hugging-face/), [Leju](/companies/leju/) and [Devanthro](/companies/devanthro/), plus InMoov, one sculptor and the people who print his files.

Five are 3D printed by design: Berkeley Humanoid Lite, ToddlerBot, InMoov, Poppy and [NimbRo-OP2X](/robots/nimbro-op2x/), the 135 cm RoboCup machine from the [University of Bonn](/companies/university-of-bonn/). Here "open" means you can make one. InMoov's record says thousands of builders have downloaded the files since 2012 and puts the parts at roughly $1,500 to $3,000, for a life-size upper body with 5-DOF tendon hands on hobby servos and Arduino boards. Poppy's kits were once sold by Generation Robots for several thousand euros; it walks with light assistance. The two 2025 machines have learned locomotion: the Berkeley Lite paper shows walking and a whole-body policy, the ToddlerBot paper walking, push-ups and manipulation trained from teleoperated demonstrations.

Two machines people assume are open are not, per the record. The original [Berkeley Humanoid](/robots/berkeley-humanoid/) of July 2024, 85 cm and 16 kg at a reported build cost under $10,000, published design details in its paper and left the open release to the Lite. The [MIT Humanoid](/robots/mit-humanoid/) has no open-source flag at all: a research prototype, not for sale.

## What you can order, and what it has proved

12 of the 24 can be ordered: 8 in stock and 4 on preorder. That is 12 of the 44 orderable humanoids in the database, about a quarter by count. Only 5 of the 12 have a verified price record: [Reachy Mini](/robots/reachy-mini/) at $299 tethered or $449 wireless, Z-Bot at $999, HopeJR at $3,000, Fourier N1 at $40,000 through the distributor Robotopian, and Reachy 2 at $70,000 to $75,000 built to order, or $38,000 for a stationary one-arm version. The four Chinese platforms in stock, [Lingxi X1](/robots/agibot-lingxi-x1/), Qinglong, Tiangong 1.0 and Tiangong 2.0, have no public price; neither does Kuavo. [K-Bot](/robots/k-scale-k-bot/) is on preorder with developer pricing we could not verify.

Now look at what those 12 have proved. 6 have something in the autonomy evidence field: Lingxi X1 with walking demos and university use, N1 with over 1,000 hours of outdoor walking claimed by Fourier, Kuavo finishing the Beijing half marathon in April 2025, Qinglong with walking, stair and manipulation demos at WAIC, OP3 playing autonomous RoboCup soccer, and Tiangong running at 6 km/h at launch. Five of those six are marked partial teleoperation; OP3 is marked no. The other 6 have nothing there, including all 4 on preorder. Reachy 2 is built for VR teleoperation: teleoperation yes, autonomy evidence empty. HopeJR is built for leader-follower teleoperation with exoskeleton arms and gloves; our price record calls it arms and hands sold as a kit, not a finished robot. Reachy Mini is a 28 cm head and torso with no arms.

Two of the 12 appear in our deployment records, both marked unclear: Kuavo's factory training work with BAIC, and Tiangong pilots in Beijing with no named commercial deployment verified. The third open machine with a deployment record is iCub: more than 30 copies in laboratories in Europe, the US and Asia according to IIT, enterprise only, historically around EUR 250,000.

## Open SDK, closed body

Ten more records describe a different kind of open: software you can call, on hardware you cannot change. 8 carry a note saying so and 2 mention an SDK in the software field. This is where most of the research fleet lives.

| Machine | cm / kg / DOF | What is open | Price in data | Status |
|---|---|---|---|---|
| [Unitree G1](/robots/unitree-g1/) | 132 / 35 / 23 | SDK, URDF models and RL environments; hardware is not | $13,500 standard, closed to your code; $43,900 EDU with SDK | In stock, backordered |
| [Unitree H1](/robots/unitree-h1/) | 180 / 47 / 19 | SDK and RL training code | From $90,000, sales conversation | Enterprise only |
| [Unitree H1-2](/robots/unitree-h1-2/) | 180 / 70 / 27 | Same SDK family as H1 and G1 | Quote only | Enterprise only |
| [Booster T1](/robots/booster-t1/) | 118 / 30 / 23 | SDK open; hardware proprietary | $29,800 basic, $50,925 with grippers | In stock via distributors |
| [EngineAI PM01](/robots/engineai-pm01/) | 138 / 40 / 24 | Open interfaces and SDK; hardware proprietary | $13,700 | In stock, Chinese marketplaces |
| [LimX TRON 1](/robots/limx-tron-1/) | 85 / 20 / n.a. | Open SDK, RL examples | $15,000 reported | In stock |
| [Rainbow RB-Y1](/robots/rainbow-rb-y1/) | n.a. / n.a. / 24 | SDK is open source | No public price | In stock |
| [IHMC Nadia](/robots/ihmc-nadia/) | n.a. | IHMC control software is open | Research platform | Not for sale |
| [HRP-2](/robots/hrp-2/) | 154 / 58 / 30 | OpenHRP control software was open | Several hundred thousand dollars, historical | Discontinued |

The [Unitree G1](/robots/unitree-g1/) is the case that matters, and we have written it up in [Unitree G1: why the cheap one cannot run your code](/blog/unitree-g1-cheap-one-cannot-run-your-code/). The short version: the SDK, URDF and RL environments are open, the $13,500 machine will not run your code, and the EDU that will starts at $43,900. The [Booster T1](/robots/booster-t1/) from [Booster Robotics](/companies/booster-robotics/) is the same deal at $29,800: open SDK, proprietary body, autonomous soccer at RoboCup 2025. You get a body that walks on day one and a user base that has already hit the bugs. You do not get the drawings, and when an actuator dies you buy the maker's.

The comparison inside the data is direct. Fourier N1 at $40,000 gives you the CAD, the BOM and the training code for a 130 cm, 38 kg, 23-DOF body. The G1 EDU at $43,900 gives you the SDK, the hands and the Jetson for a 132 cm, 35 kg, 23-DOF body you cannot modify. Same size and price, opposite ideas of what you are paying for. [HumanPlus](/robots/humanplus/) shows the third way: Stanford took a closed [Unitree H1](/robots/unitree-h1/), added hands, released the code and the modifications, and trained shoe-wearing and folding from shadowed demonstrations. Open research on a closed base is how most papers get written.

## Build, kit or SDK

Build from files if you have a printer, a small workshop and time, and your goal is to understand the machine or change it. Berkeley Humanoid Lite, under $5,000 in parts with a paper behind it, is the benchmark; ToddlerBot at about $6,000 adds manipulation and a teleoperation pipeline; InMoov at $1,500 to $3,000 is an upper body for a school or a maker, on a non-commercial licence. All three are not for sale, because you are the factory.

Buy a kit if you want open hardware without the printing. Reachy Mini at $299 is a head on a desk and the cheapest door into the Hugging Face stack. Z-Bot at $999 and HopeJR at $3,000 are preorders from companies that publish their designs and have shown no autonomous work. OP3 is the proven one: 51 cm, 3.5 kg, 20 DOF, a ROS-based open framework, in stock at a price you ask for. Reachy 2 at $70,000 is the only full open stack sold assembled, and it rolls rather than walks.

Buy closed hardware with an SDK if what you need is a body that already walks and a fleet of other users: the G1 EDU at $43,900, the T1 at $29,800, the PM01 at $13,700 or the TRON 1 at $15,000. Then read the licence on that SDK too, and count the repair path: an open machine you fix with a printer, a closed one with a purchase order. Decide which you are set up for before you decide on the robot.

## Sources

- [Berkeley Humanoid Lite](https://lite.berkeley-humanoid.org/), UC Berkeley
- [ToddlerBot](https://toddlerbot.github.io/), Stanford University
- [InMoov](https://inmoov.fr/), InMoov
- [Poppy Humanoid](https://www.poppy-project.org/en/robots/poppy-humanoid/), Poppy Project
- [ROBOTIS OP](https://emanual.robotis.com/docs/en/platform/op3/introduction/), Robotis
- [Fourier N1 open source page](https://www.fftai.com/products-n1), Fourier
- [Reachy 2, the open-source humanoid for embodied AI](https://pollen-robotics.com/reachy-2/), Pollen Robotics
- [Unitree G1 product page](https://shop.unitree.com/products/unitree-g1), Unitree