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| K-Scale Labs | |
|---|---|
| General information | |
| Full name | K-Scale Labs, Inc. |
| Founded | 2024 |
| Founders | Benjamin Bolte, Matthew Freed, Pawel Budzianowski |
| Headquarters | Palo Alto, California, United States |
| Industry | Robotics, Open-source hardware |
| Products | K-Bot, Z-Bot |
| Total funding | ~$4.75 million |
| Status | Defunct (November 2025) |
| Website | kscale.dev (archived) |
K-Scale Labs was an American robotics startup that developed open-source humanoid robots. Based in Palo Alto, California, the company was backed by Y Combinator and positioned itself as a builder of affordable, hackable humanoid platforms for developers, researchers, and hobbyists. K-Scale Labs shut down in November 2025 after failing to secure additional funding, having shipped only two units of its flagship K-Bot robot before ceasing operations.[1][2]
K-Scale Labs was founded in 2024 by Benjamin Bolte, a former senior engineer at Tesla who wrote the CUDA code for the voxel occupancy network behind the Tesla Optimus perception model, and who later worked on Meta's AI research team. Co-founders included Matthew Freed, who had built advanced robotics systems at Lockheed Martin and General Dynamics, and Pawel Budzianowski, a machine learning researcher with a Ph.D. from the University of Cambridge.[3][4]
The company's name referenced the Kardashev Scale, an astrophysics framework measuring a civilization's technological advancement. Bolte described K-Scale's mission as "building infrastructure to make humanity into a Type I Kardashev civilization."[4]
K-Scale Labs entered Y Combinator's Winter 2024 batch and raised $500,000 in pre-seed funding from Lombardstreet Ventures and Y Combinator. The company subsequently raised approximately $4.75 million across seed rounds from GFT Ventures, Pioneer Fund, AI Grant, and Lux Capital. OpenAI's nonprofit arm donated $250,000 to support K-Scale's open-source efforts, and OpenAI CEO Sam Altman reportedly pre-ordered a K-Bot unit.[5][6]
Before K-Bot, K-Scale developed an early prototype called Stompy (designated Zeroth-01), introduced in February 2024. Stompy was a 122-centimeter-tall humanoid built with a total bill of materials under $10,000. The team designed it during the YC batch, building five hardware iterations over three months. Each component was designed to fit on a standard 256 x 256 mm 3D printer bed, and all CAD files, assembly guides, and bills of materials were made publicly available.[4][7]
K-Scale began shipping Founder's Edition units of K-Bot in October 2025 at $8,999 for the first 100 units. However, in November 2025, the company announced it was ceasing operations after failing to secure a lead investor for additional funding. At the time, K-Scale had less than one month of runway remaining, with approximately $400,000 in cash reserves. Only two K-Bot units were delivered before all remaining preorder deposits were refunded and most of the team was laid off.[1][2]
A post-mortem analysis identified several strategic errors: the company spent months working on locomotion challenges while competitors shipped demonstrations, missing fundraising windows. Supply chain management proved difficult, with contract manufacturing costs in China varying from $800 to $2,400 per unit depending on execution quality.[8]
| Model | Height | Price | Target audience | Status |
|---|---|---|---|---|
| Stompy (Zeroth-01) | 122 cm | ~$10,000 (BOM) | Prototype/proof of concept | Discontinued |
| Z-Bot | 46 cm | ~$999 (assembled); $350 (DIY kit) | Students, hobbyists | Kickstarter launched 2025 |
| K-Bot | 140 cm | $8,999 | Researchers, developers | Discontinued (2 units shipped) |
| Specification | Value |
|---|---|
| Height | 140 cm (4 ft 7 in) |
| Weight | 34 kg (77 lbs) |
| Degrees of freedom | 20 |
| Payload capacity | 10 kg |
| Battery life | Up to 4 hours |
| Onboard computer | Raspberry Pi 5 |
| Operating system | K-OS (Rust-based) |
| Peak torque (max) | 120 Nm |
K-Scale Labs developed a comprehensive open-source software ecosystem:
| Component | License |
|---|---|
| Hardware designs | CERN-OHL-S-2.0 |
| Software (K-OS) | MIT License |
| Software (other) | GPL v3 |
Upon shutdown, K-Scale released all remaining proprietary intellectual property under open-source licenses, preserving the project's designs for the broader robotics community.[10]
Following K-Scale's closure, co-founder Jingxiang Mo established Gradient Robotics in Menlo Park, California, describing the new venture as having "inherited the K-Scale spirit, mission, and core engineering team." Gradient Robotics closed a pre-seed funding round in September 2025.[11]