Datasheet for local AI49 models98 GPUsData read 2026-09-25
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Wan 2.1 T2V 14B on 20 GB of VRAM

Video model · 14BAny 20 GB GPUData 2026-09-25
Runs well
Yes — and comfortably.

Download FP8 (14.3 GB). With the model's working memory it needs about 18.6 GB, leaving 1.4 GB spare on 20 GB. Quality: practically identical to the original.

Best fileFP8
File size14.3 GB
VRAM needed~18.6 GB
System RAM32 GB+
Memory map · 20 GB GPU18.6 GB / 20 GB
010 GB20 GB
Weights FP8 · 14.3 GBWorking memory · 3.5 GBReserve · 0.8 GBFree · 1.4 GB
calculated from real file sizes plus working memory. Not yet measured on this setup. How this works.

On RTX 40 and RTX 50 GPUs take the FP8 file instead of Q8_0: same class, faster there. On older NVIDIA, AMD and Intel GPUs Q8_0 is the better 8-bit file.

01What to download

PartFileFolderSize
Modelwan2.1_t2v_14B_fp8_e4m3fn.safetensors
FP8 · Comfy-Org/Wan_2.1_ComfyUI_repackaged
models/diffusion_models14.3 GBDownload →
Text encoderumt5_xxl_fp8_e4m3fn_scaled.safetensors
UMT5-XXL FP8 (scaled) · Comfy-Org/Wan_2.1_ComfyUI_repackaged
models/text_encoders6.7 GBDownload →
VAEwan_2.1_vae.safetensors
Wan 2.1 VAE · Comfy-Org/Wan_2.1_ComfyUI_repackaged
models/vae0.3 GBDownload →
Total download · keep about the same free on disk21.3 GB

Alternatives: UMT5-XXL FP16 (11.4 GB). The 16-bit text encoder is a little more faithful; the smaller one is chosen here because it loads faster and needs less RAM. Sizes read from Hugging Face (2026-09-25). “Download” links start the file directly; the file name links are the same files the official ComfyUI workflows use.

System RAM: 32 GB or more. ComfyUI keeps the model file, the text encoder and the VAE in system RAM and moves them to the GPU as needed. With this set of files that is about 21.3 GB, plus roughly 6 GB for Windows, ComfyUI and a browser: 27.3 GB in total. With less RAM it still runs, but Windows starts swapping to disk and loading gets very slow. calculated

02Every file, on 20 GB

FileSizeNeededOn this cardQualityDownload
16-bit
SAFETENSORS · Comfy-Org
28.6 GB32.9 GB12.9 GB too bigthe original weightsHugging Face →
Q8_0
GGUF · city96
15.9 GB20.2 GBspills 0.2 GBpractically identical to the originalHugging Face →
FP8 ←
SAFETENSORS · Comfy-Org
14.3 GB18.6 GBfits · 1.4 GB sparepractically identical to the originalHugging Face →
Q6_K
GGUF · city96
12.5 GB16.8 GBfits · 3.2 GB sparevery close to the originalHugging Face →
Q5_K_M
GGUF · city96
11.3 GB15.6 GBfits · 4.4 GB spareclose; small differences in fine detailHugging Face →
Q4_K_M
GGUF · city96
10.1 GB14.4 GBfits · 5.6 GB sparegood; some loss in fine detail and textHugging Face →
Q3_K_M
GGUF · city96
7.6 GB11.9 GBfits · 8.1 GB sparenoticeable loss of detailHugging Face →

Sizes from the Hugging Face file listing, read 2026-09-25. “Needed” = file + 3.5 GB working memory for this model + 0.8 GB kept free for the system.

03The text encoder

UMT5-XXL: 11.4 GB as 16-bit, 6.7 GB as FP8, 3.7 GB as GGUF Q4_K_M. ComfyUI encodes the prompt first and can push the encoder out of VRAM before sampling, so it does not have to fit together with the model. On 20 GB the FP8 encoder fits on its own, so prompt encoding stays fast.