Ternary Bonsai 2 27B logo

Ternary Bonsai 2 27B

PrismML · Released Sep 2026

Conditional

Ternary Bonsai 2 27B squeezes Qwen3.8 27B into about 5.9GB at 1.76 effective bits, so a 262K-context text-and-image model fits on a Mac or a single consumer GPU under Apache 2.0. Conditional because the quality figures are PrismML's own, its blog and model card report different aggregate scores, and the files need PrismML's custom kernels: stock llama.cpp will not run them. Right for local-inference users short on memory.

Is it right for you?

Good for

  • Running a 27B-class model in about 6GB: the ternary GGUF is 5.95GB against a 53.8GB FP16 reference, plus a 0.63GB projector for image input
  • Apple silicon Macs: PrismML reports 46.8 tokens per second on an M5 Max through MLX
  • Long-context local work with a 262K-token window
  • Commercial use and redistribution under Apache 2.0

Not good for

  • Standard local tooling: the GGUF files need PrismML's llama.cpp fork, and stock llama.cpp will not run them
  • Maximum quality: PrismML's own figures put it at 98.2% of full-precision Qwen3.8 27B
  • Decisions that need independent evaluations: all published scores are PrismML's

Pricing

Input

Free (open weights)

Output

Free (open weights)

Context

262K ctx; self-hosted; PrismML kernels required

View full pricing

Benchmarks

BenchmarkScoreSource
Aggregate retention vs Qwen3.8 27B full precision (PrismML, thinking mode)98.2% Source
Math category (PrismML, thinking mode)96.57 Source
Decode speed, Apple M5 Max (PrismML)46.8 tok/s Source

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How we evaluate