K-Scale Labs

A US startup building affordable, open-source humanoid robots, which shut down in November 2025.

K-Scale Labs was founded in Palo Alto, California in 2024 by Benjamin Bolte, backed by Y Combinator; Bolte had previously worked at Meta FAIR and on Tesla's Autopilot team. The company set out to build open-source humanoid robots that ordinary developers could afford and modify themselves: the roughly 1.4-meter K-Bot was priced at about $9,000 for developers, the 46-centimeter desktop humanoid Z-Bot was about $999, and it open-sourced the MuJoCo-and-JAX-based reinforcement-learning training library ksim and the inference-export tool kinfer. On November 4, 2025, Bolte wrote to customers saying fundraising had fallen through, canceled all K-Bot preorders with refunds, laid off most of the staff, and released all its designs under an open-source license. It is often cited in discussions of the open-source-hardware approach and the funding barrier to mass production.

ExampleK-Bot's parts were designed to be manufactured on a 3D printer with a 256×256 mm print bed, with a reported materials cost under $10,000.

Also called

K-Scale

Related

Humanoid Robot · Open-Source Hardware (OSHW) · Small-size Humanoid Robot · MuJoCo (Multi-Joint dynamics with Contact) · JAX · Mass Production

Sources

Humanoids Daily: K-Scale Labs Cancels K-Bot Orders, Open-Sources All IP
Mike Kalil: K-Scale Labs Disrupts Silicon Valley with Open-Source Humanoids
The Robot Report: 6 lessons I learned watching a robotics startup die

As of

2025-11