Neuralink has achieved some impressive breakthroughs by surgically implanting receptors into people’s brains, but a Silicon Valley startup is now looking to do similar things a lot more simply — by just wearing a cap.
Sabi, a California-based brain-computer interface (BCI) startup, has emerged from stealth with a bold proposition: a beanie-style wearable that reads your brain signals and converts your thoughts into on-screen text, no surgery required. In an industry long dominated by invasive implants and bulky lab headsets, Sabi is betting that the future of human-computer interaction looks a lot more like everyday fashion.
A Beanie That Reads Your Mind
Developed by Sabi, the prototype uses brain-computer interface technology to convert a user’s internal speech into text, effectively allowing users to “type” using their thoughts. The device is designed to be one of the least intrusive brain-tech wearables yet, avoiding the bulky, futuristic look of many experimental headsets, and instead blending into everyday clothing to make it more practical for daily use.
The beanie is packed with between 70,000 and 100,000 ultra-dense EEG sensors, designed to capture neural activity through the scalp. The core target is “imagined speech” — the internal monologue that runs through your head — which is decoded and converted into real-time text on a connected device.
“Given that high-density sensing, it pinpoints exactly what and where neural activity is happening. We use that information to get much more reliable data to decode what a person is thinking,” said CEO Rahul Chhabra.
Early targets suggest typing speeds of around 30 words per minute, with the potential to improve as users become more familiar with the system — opening up new use cases, from accessibility tools for people with disabilities to hands-free computing for everyday users.
The Brain Foundation Model
What makes Sabi’s technical approach particularly ambitious is not just the hardware, but the AI powering it. To power the interface, Sabi has trained a “brain foundation model” using 100,000 hours of neural data collected from 100 volunteers. The goal is to build models that can generalize across users — accounting for the reality that brain signals differ from person to person, and even the same thought can produce slightly different neural patterns each time.
The device is also designed to work out of the box without requiring daily calibration, which has been a major limitation for many BCI systems. On the privacy front, Sabi promises end-to-end encryption and claims their AI can train on encrypted data, so raw brain signals aren’t exposed. They are also working with neurosecurity experts for independent audits.
How It Stacks Up Against Neuralink
The comparison to Neuralink is inevitable, and Sabi leans into it. While Elon Musk’s company has made headlines with its surgically implanted chips — enabling paralyzed patients to control computers with their minds — the procedure requires opening the skull. Sabi’s approach is based on electroencephalography (EEG), a technique for recording electrical activity from the brain using sensors placed on the scalp, requiring no surgery whatsoever.
That distinction matters enormously when thinking about scale. Vinod Khosla, founder of Khosla Ventures and one of Sabi’s investors, put it plainly: “The biggest and baddest application of BCI is if you can talk to your computer by thinking about it. If you’re going to have a billion people use BCI for access to their computers every day, it can’t be invasive.”
The Founder: From BITS Pilani to Silicon Valley
At the center of Sabi is Rahul Chhabra, a co-founder and CEO whose path to building a mind-reading beanie winds through some of India’s and America’s most prestigious academic and entrepreneurial institutions. A graduate of the Birla Institute of Technology and Science (BITS), Pilani — one of India’s most competitive engineering universities — Chhabra showed an early aptitude for both technical depth and leadership. At BITS Pilani, he led Conquest, India’s first student-run startup accelerator, and also conducted research at Stanford University on event data series prediction using machine learning.
Before Sabi, Chhabra co-founded Hallparty, a fintech and campus infrastructure platform that scaled to serve one million students across 91 Delhi University colleges, eventually being adopted by the Indian government and the Payment Council of India. That experience — building hardware, software, and institutional partnerships simultaneously — appears to have shaped his approach at Sabi, where the challenge is equally as multifaceted.
Sabi is backed by a serious roster of investors, including Khosla Ventures, Accel, Initialized Capital, and Kevin Weil, the former Chief Product Officer at OpenAI — a signal that the company’s ambitions are being taken seriously in Silicon Valley’s highest circles.
Challenges on the Road Ahead
Despite the excitement, the road to a consumer-ready thought-controlled computer is not without its obstacles. Brain signals vary widely between individuals, and even the same thought can produce slightly different neural patterns each time. To address this, Sabi is developing a large-scale AI model trained on thousands of hours of brain data collected from volunteers, aiming to identify patterns that correspond to internal speech across different users.
The initial winter-hat design is slated for release by late 2026, with plans for a more streamlined baseball cap version to follow. Whether the company can meet that timeline — and deliver on its technical promises — will be closely watched by researchers, investors, and rivals alike.
The core idea is a tantalizing one: typing by thought alone, with a wearable that could redefine productivity and communication, and make BCI technology accessible to all — not just patients in clinical trials or early adopters willing to go under the knife. If Sabi succeeds, the keyboard may one day seem as antiquated as the telegraph.