by janhq
Open source · 111k downloads · 52 likes
Jan v3 4B base instruct is a compact language model with 4 billion parameters, designed as an optimized base for fine-tuning and lightweight programming assistance. Derived from post-training distillation from a larger teacher model, it maintains strong general performance while offering improved instruction-following capabilities right out of the box. Thanks to its reduced size and efficient architecture, it stands out as an ideal starting point for custom adaptations or tasks requiring code assistance. The model particularly excels in environments where lightness and responsiveness are critical, while remaining versatile for a wide range of applications. It is accessible via the Jan application, which simplifies local deployment or online use.

Jan-v3-4B-base-instruct is a 4B-parameter model obtained via post-training distillation from a larger teacher, transferring capabilities while preserving general-purpose performance on standard benchmarks. The result is a compact, ownable base that is straightforward to fine-tune, broadly applicable and minimizing the usual capacity–capability trade-offs.
Building on this base, Jan-Code, a code-tuned variant, will be released soon.
This repo contains the BF16 version of Jan-v3-4B-base-instruct, which has the following features:
Intended Use

Jan-v3 demo is hosted on Jan Browser at chat.jan.ai. It is also optimized for direct integration with Jan Desktop, select the model in the app to start using it.
Using vLLM:
vllm serve janhq/Jan-v3-4B-base-instruct \
--host 0.0.0.0 \
--port 1234 \
--enable-auto-tool-choice \
--tool-call-parser hermes
Using llama.cpp:
llama-server --model Jan-v3-4B-base-instruct-Q8_0.gguf \
--host 0.0.0.0 \
--port 1234 \
--jinja \
--no-context-shift
For optimal performance in agentic and general tasks, we recommend the following inference parameters:
temperature: 0.7
top_p: 0.8
top_k: 20
Updated Soon