Qwen · vision language

Qwen3-VL-4B-Thinking

Qwen/Qwen3-VL-4B-Thinking

Qwen3-VL-4B-Thinking at Q4_K_M is exactly 2,497,281,472 bytes (2.33 GiB / 2.50 GB) — an effective 4.502 bits per weight, not the nominal 4. Its KV cache at 32K is 4.50 GiB.

From the file· summed from 1 file(s)From the file· KV per layer
Parameters
4.4B
Architecture
qwen3vl
36 layers
Context
262,144
native (config.json)
License
apache-2.0

Shipped quantizations

exact bytes, summed from published files
QuantSizeExact bytesEffective bpwTensorsPublisher
UD-IQ1_S1.01 GiB1,083,151,6161.953unsloth
UD-IQ1_S1.01 GiB1,083,151,7761.953unsloth
UD-IQ1_M1.06 GiB1,143,485,6962.061unsloth
UD-IQ1_M1.06 GiB1,143,485,8562.061unsloth
UD-IQ2_XXS1.17 GiB1,255,347,4562.263unsloth
UD-IQ2_XXS1.17 GiB1,255,347,6162.263unsloth
UD-IQ2_M1.43 GiB1,530,404,0962.759unsloth
UD-IQ2_M1.43 GiB1,530,404,2562.759unsloth
Q2_K1.55 GiB1,669,501,6963.010unsloth
Q2_K_L1.55 GiB1,669,501,6963.010unsloth
Q2_K1.55 GiB1,669,501,8563.010unsloth
Q2_K_L1.55 GiB1,669,501,8563.010unsloth
UD-IQ3_XXS1.56 GiB1,674,378,4963.018unsloth
UD-IQ3_XXS1.56 GiB1,674,378,6563.018unsloth
Q3_K_S1.76 GiB1,886,999,2963.402unsloth
Q3_K_S1.76 GiB1,886,999,4563.402unsloth
Q3_K_M1.93 GiB2,075,620,0963.742unsloth
Q3_K_M1.93 GiB2,075,620,2563.742unsloth
IQ4_XS2.11 GiB2,270,753,5364.093unsloth
IQ4_XS2.11 GiB2,270,753,6964.093unsloth
Q4_02.21 GiB2,375,774,9764.283unsloth
Q4_02.21 GiB2,375,775,1364.283unsloth
IQ4_NL2.22 GiB2,381,345,5364.293unsloth
IQ4_NL2.22 GiB2,381,345,6964.293unsloth
Q4_K_S2.22 GiB2,383,311,6164.296unsloth
Q4_K_S2.22 GiB2,383,311,7764.296unsloth
Q4_K_M2.33 GiB2,497,281,4724.502Qwen
Q4_K_M2.33 GiB2,497,282,8164.502unsloth
Q4_K_M2.33 GiB2,497,282,9764.502unsloth
Q4_12.42 GiB2,596,631,2964.681unsloth
Q4_12.42 GiB2,596,631,4564.681unsloth
Q5_K_S2.63 GiB2,823,713,5365.090unsloth
Q5_K_S2.63 GiB2,823,713,6965.090unsloth
Q5_K_M2.69 GiB2,889,515,7765.209unsloth
Q5_K_M2.69 GiB2,889,515,9365.209unsloth
Q6_K3.08 GiB3,306,263,2965.960unsloth
Q6_K3.08 GiB3,306,263,4565.960unsloth
Q8_03.99 GiB4,280,405,9527.716Qwen
Q8_03.99 GiB4,280,407,2967.716unsloth
Q8_03.99 GiB4,280,407,4567.716unsloth

KV cache by context

computed per layer
ContextKV cache (f16)Flat formulaOverstated byFull / windowed / recurrent
4,0960.56 GiB0.56 GiB36 / 0 / 0
8,1921.13 GiB1.13 GiB36 / 0 / 0
16,3842.25 GiB2.25 GiB36 / 0 / 0
32,7684.50 GiB4.50 GiB36 / 0 / 0
65,5369.00 GiB9.00 GiB36 / 0 / 0
131,07218.00 GiB18.00 GiB36 / 0 / 0

Compare with

same modality, comparable size

Will it run on your card?

full quant x context sweep

Why other calculators give a different number

A parameters × bits ÷ 8 estimate puts Q4_K_M at roughly 2.32 GiB. The real file is 2.33 GiB, because a quantization is a mixture and some tensors are always kept at higher precision.

Architecture

from config.json
Layers
36
Attention heads
32
KV heads
8
Head dim
128
Hidden size
2560
Vocab
151,936
Sliding window
none
SWA period
MLA
no
Experts
Experts per token
use_sliding_window

Questions people ask

How much VRAM does Qwen3-VL-4B-Thinking need?
Q4_K_M is exactly 2,497,281,472 bytes (2.33 GiB) in weights. Add the KV cache, which depends on your context length, plus roughly half a gigabyte of runtime overhead.
How large is Qwen3-VL-4B-Thinking's KV cache?
4.50 GiB at 32K context with an f16 cache, computed per layer. Quantizing the cache to q8_0 roughly halves it, which is often the difference between a context length fitting and not.
Which quantization of Qwen3-VL-4B-Thinking should I use?
Q4_K_M is the usual default. Pick the largest quantization that fits your card at the context you actually need — the table above gives exact sizes for every one published.