Ternary Bonsai

1.58-bit LLMs that fit in 1.75 GB — runs in your browser via WebGPU

PrismML's Ternary Bonsai is a family of ultra-compressed language models using 1.58-bit weights — meaning every parameter is stored as -1, 0, or +1, with no higher-precision layers anywhere in the architecture. The line-up covers 8B, 4B, and 1.7B parameter models. The flagship 8B model fits in 1.75 GB of RAM, a 9x reduction versus a 16-bit baseline. Unlike earlier 1-bit experiments that felt like a party trick with serious capability regressions, Ternary Bonsai 8B outperforms PrismML's own prior 1-bit Bonsai 8B by 5 points on average across standard benchmarks. The team also ships WebGPU inference, so the 1.7B model runs entirely in a browser tab. This is the first time a production-quality chat model has run with no server at all. The real-world use case is edge and offline deployment: medical devices, air-gapped government systems, consumer apps that need to work without a signal. At 1.75 GB, the 8B model fits on the GPU RAM of a six-year-old gaming laptop. PrismML is positioning this as the foundation for truly offline AI — a credible claim if the capability benchmarks hold up under real-world testing.

Panel Reviews

The Builder

Developer Perspective

Ship

“1.75 GB for an 8B model is a genuine engineering achievement. I can finally ship a capable model inside a desktop Electron app without requiring users to have a dedicated GPU. The WebGPU demo loads fast and output quality is surprisingly coherent for its size.”

The Skeptic

Reality Check

Skip

“Benchmarks are one thing; real task performance is another. A 9x memory saving typically comes with a 15-30% quality drop on anything beyond simple Q&A. And 'scores 5 points higher than our previous 1-bit model' is a low bar when the previous model wasn't competitive with 4-bit quants.”

The Futurist

Big Picture

Ship

“Browser-native LLMs with no server change the entire privacy calculus. If this scales to 13B+ parameter territory at comparable compression ratios, every personal AI assistant can run offline on consumer hardware. That's a trajectory worth tracking closely.”

The Creator

Content & Design

Ship

“WebGPU inference means I can build offline creative tools — grammar checkers, caption writers, image prompt expanders — without an API key or monthly cost. The 1.7B model is small enough to embed in a browser extension with manageable download size.”