Is NVIDIA-Nemotron-3-Nano-4B-BF16 or Qwen3-4B smaller?

Qwen3-4B is smaller at Q4_K_M: 2.33 GiB against 2.64 GiB.

Which uses less memory at long context?

Qwen3-4B — its KV cache at 32K context is 1.2x smaller, because of how its attention layers cache.

Model comparison

NVIDIA-Nemotron-3-Nano-4B-BF16 vs Qwen3-4B

At Q4_K_M, Qwen3-4B is the smaller download — 2,497,280,256 bytes against 2,837,072,896. At long context the gap widens: Qwen3-4B's KV cache at 32K is 1.2× smaller, which usually matters more than the difference in weights.

From the file· summed bytes, KV per layer

Side by side

	NVIDIA-Nemotron-3-Nano-4B-BF16	Qwen3-4B
Parameters	4.0B	4.0B
Architecture	nemotron_h	qwen3
Layers	42	36
Native context	262,144	40,960
Mixture of experts	no	no
Quantizations published	42	29
Smallest quantization	2.03 GiB	1.01 GiB
Q4_K_M	2.64 GiB	2.33 GiB
Licence	other	—

KV cache by context

the term that decides long-context viability

Context	NVIDIA-Nemotron-3-Nano-4B-BF16	Qwen3-4B	Ratio
4,096	0.66 GiB	0.56 GiB	1.17×
8,192	1.31 GiB	1.13 GiB	1.17×
16,384	2.63 GiB	2.25 GiB	1.17×
32,768	5.25 GiB	4.50 GiB	1.17×
65,536	10.50 GiB	9.00 GiB	1.17×
131,072	21.00 GiB	18.00 GiB	1.17×