How much VRAM do I need for FLUX and Stable Diffusion XL?
Short answer: Stable Diffusion XL’s FP16 weights are about 7 GB (CloudGPU model page, read 2026-10-23). FLUX.1 (dev or schnell) has about 24 GB of weights at 16-bit and about 12-16 GB at FP8 (CloudGPU model page, read 2026-10-23); with the text encoders and VAE loaded, the 16-bit pipeline is about 31 GB (Hugging Face Diffusers blog, read 2026-10-23). VRAM need depends on model, precision and workflow: larger resolutions, ControlNet, LoRAs, upscalers and larger batches add to it.
Published figures
From CloudGPU’s model pages (VRAM figures dated 2026-09-08; page re-read 2026-10-23). The FLUX figures refer to the main model weights, not the whole pipeline:
| Model | FP16 | Lower precision |
|---|---|---|
| Stable Diffusion XL | about 7 GB | n/a |
| FLUX.1 dev | about 24 GB (weights) | about 12-16 GB at FP8 |
| FLUX.1 schnell | about 24 GB (weights) | about 12-16 GB at FP8 |
What changes the number
- Resolution and batch size: larger images and batches use more VRAM.
- ControlNet, IP-Adapter, LoRAs: each adds memory.
- Text encoders: FLUX uses large text encoders (the T5-XXL FP16 file alone is about 9.8 GB on Hugging Face, read 2026-10-23); they are loaded alongside the main model unless you offload them. The FLUX.1-dev files add up to about 34 GB (23.8 GB main model, 9.8 GB T5, 0.25 GB CLIP, 0.34 GB VAE; Hugging Face file sizes, read 2026-10-23), and the Hugging Face Diffusers blog (read 2026-10-23) reports about 31.4 GB loaded in BF16.
- Precision: FP8 roughly halves the main model’s memory with some quality trade-offs.
Choosing a card
VRAM need depends on model, precision and workflow. Start from the figures above, add what your workflow loads, and check peak VRAM with nvidia-smi on a first run. Offloading the text encoders lowers VRAM use at the cost of speed.
Check https://cloudgpu.app/deploy for the cards you can start now.
Using the ComfyUI template
Check the template description on https://cloudgpu.app/deploy to see whether FLUX weights are included; if they are not, download the FLUX model, text encoders and VAE after the instance is ready. Instance storage is limited, so check the size first: the full 16-bit FLUX.1-dev files take about 34 GB together (Hugging Face file sizes, read 2026-10-23: 23.8 GB model, 9.8 GB T5 text encoder, 0.25 GB CLIP, 0.34 GB VAE), so FP8 files take less space if you also want other checkpoints. See how to choose a rental GPU for ComfyUI.
Billing reminder
Startup takes about 2 minutes. Billing is per minute, rounded up, 1-minute minimum, and the instance is billed while a model downloads. See how per-minute billing works.
Frequently asked questions
How much VRAM does SDXL need?
About 7 GB for the FP16 weights (the Hugging Face SDXL base file is 6.94 GB, read 2026-10-23). Larger resolutions, batches and add-ons need more.
How much VRAM does FLUX.1 dev need?
About 24 GB for the 16-bit weights (about 31 GB with text encoders and VAE loaded) and about 12-16 GB at FP8, per CloudGPU’s model page and the Hugging Face Diffusers blog (read 2026-10-23).
Is FLUX.1 schnell lighter than dev?
Not by much. CloudGPU’s published VRAM figures (read 2026-10-23) are the same, about 24 GB at 16-bit and about 12-16 GB at FP8, and the Hugging Face weight files are of similar size.
Will instance storage hold FLUX?
Check your instance’s storage size first. Full 16-bit FLUX.1-dev files total about 34 GB (Hugging Face file sizes, read 2026-10-23), which leaves limited space for other models; FP8 files are smaller.
Is FLUX included in the ComfyUI template?
Check the template description on https://cloudgpu.app/deploy. If the weights are not included, download them after the instance starts.
Sources (read 2026-10-23, Asia/Shanghai)
- CloudGPU model pages: https://cloudgpu.app/run/flux-1-dev , https://cloudgpu.app/run/stable-diffusion-xl (VRAM figures dated 2026-09-08 by CloudGPU)
- FLUX.1-dev file sizes on Hugging Face (flux1-dev.safetensors 23.8 GB, ae.safetensors 0.34 GB, t5xxl_fp16 9.79 GB, clip_l 0.25 GB): https://huggingface.co/black-forest-labs/FLUX.1-dev and https://huggingface.co/comfyanonymous/flux_text_encoders
- Hugging Face blog, “Exploring Quantization Backends in Diffusers” (loading FLUX.1-dev in BF16 needs about 31.4 GB): https://huggingface.co/blog/diffusers-quantization
- Stable Diffusion XL base 1.0 files (sd_xl_base_1.0.safetensors 6.94 GB): https://huggingface.co/stabilityai/stable-diffusion-xl-base-1.0
- Figures marked “estimate” are sums of the file sizes above and exclude activations; real usage depends on resolution, batch size, offloading and the software used.
The Deploy page lists the cards you can start. Prices are on https://cloudgpu.app/pricing and are not repeated here.
Last updated: 2026-10-23 (Asia/Shanghai).