Is LFM2-1.2B or Qwen3-1.7B smaller?

LFM2-1.2B is smaller at Q4_K_M: 0.68 GiB against 1.03 GiB.

Which uses less memory at long context?

LFM2-1.2B — its KV cache at 32K context is 3.5x smaller, because of how its attention layers cache.

Model comparison

LFM2-1.2B vs Qwen3-1.7B

At Q4_K_M, LFM2-1.2B is the smaller download — 730,893,024 bytes against 1,107,409,472. At long context the gap widens: LFM2-1.2B's KV cache at 32K is 3.5× smaller, which usually matters more than the difference in weights.

From the file· summed bytes, KV per layer

Side by side

	LFM2-1.2B	Qwen3-1.7B
Parameters	1.2B	2.0B
Architecture	lfm2	qwen3
Layers	16	28
Native context	128,000	40,960
Mixture of experts	no	no
Quantizations published	40	48
Smallest quantization	0.45 GiB	0.50 GiB
Q4_K_M	0.68 GiB	1.03 GiB
Licence	other	—

KV cache by context

the term that decides long-context viability

Context	LFM2-1.2B	Qwen3-1.7B	Ratio
4,096	0.13 GiB	0.44 GiB	3.50×
8,192	0.25 GiB	0.88 GiB	3.50×
16,384	0.50 GiB	1.75 GiB	3.50×
32,768	1.00 GiB	3.50 GiB	3.50×
65,536	2.00 GiB	7.00 GiB	3.50×
131,072	4.00 GiB	14.00 GiB	3.50×