| --- |
| license: other |
| language: |
| - en |
| pipeline_tag: text-to-image |
| tags: |
| - flux |
| - flux2 |
| - webgpu |
| - onnx |
| - onnxruntime |
| - image-generation |
| - text-to-image |
| - lowbit |
| base_model: black-forest-labs/FLUX.2-klein-4B |
| library_name: onnxruntime |
| --- |
| |
| # FLUX.2 Klein 4B WebGPU Low-Bit Bundle |
|
|
| This is the browser model bundle for the static FLUX.2 WebGPU app at |
| [ryanhlewis/flux2-webgpu](https://huggingface.co/spaces/ryanhlewis/flux2-webgpu). |
| It is derived from `black-forest-labs/FLUX.2-klein-4B` and the ONNX WebGPU q4 |
| bundle by `MarkShark2/flux2-klein-4b-onnx-webgpu-q4`, with an additional custom |
| low-bit WebGPU transformer runtime payload used by |
| [ryanhlewis/flux2-webgpu](https://github.com/ryanhlewis/flux2-webgpu). |
|
|
| ## Contents |
|
|
| | Component | Size | |
| | --- | ---: | |
| | Custom low-bit transformer assets | 7.27 GB / 6.77 GiB | |
| | Upstream q4 text encoder and ONNX transformer fallback | 5.13 GB / 4.77 GiB | |
| | VAE decoder/encoder, tokenizer, config overlay | 0.18 GB / 0.17 GiB | |
| | Precomputed default prompt context/projection | 0.01 GB / 0.01 GiB | |
| | Total staged model repository payload | 12.58 GB / 11.72 GiB | |
|
|
| The default static UI uses the custom low-bit transformer path. Arbitrary prompts |
| require the q4 text encoder. The q4 ONNX transformer files are included as a |
| fallback path, but the app defaults to the custom low-bit transformer runtime. |
|
|
| ## Static Browser Use |
|
|
| Serve the app files from the GitHub repository or the linked Static Space and set: |
|
|
| ```js |
| globalThis.FLUX2_MODEL_BASE_URL = "https://huggingface.co/ryanhlewis/flux2-klein-4b-webgpu-lowbit/resolve/main"; |
| globalThis.FLUX2_RUNTIME_BASE_URL = globalThis.FLUX2_MODEL_BASE_URL; |
| globalThis.FLUX2_CUSTOM_KERNEL_BASE_URL = `${globalThis.FLUX2_MODEL_BASE_URL}/custom_lowbit`; |
| ``` |
|
|
| No Python, Gradio server, CUDA, or ROCm runtime is required for generation in the |
| Static Space. The user's browser downloads model files and runs inference locally |
| through WebGPU. |
|
|
| ## Benchmarks |
|
|
| Local headed Chrome/Edge WebGPU benchmarks on the development machine, after |
| background preparation, with result cache disabled, default prompt, fixed seeds, |
| custom low-bit WebGPU backend, and exact full-resolution render/decode: |
|
|
| | Size | Browser elapsed | Transformer | VAE | Notes | |
| | ---: | ---: | ---: | ---: | --- | |
| | 256x256 | 0.817s | 0.603s | 0.213s | exact | |
| | 512x512 | 4.438s | 2.922s | 1.514s | exact | |
| | 768x768 | 10.723s | 8.009s | 2.712s | exact | |
| | 1024x1024 | 45.434s | 24.108s | 21.324s | exact, VAE-heavy | |
|
|
| These are browser WebGPU numbers, not PyTorch/CUDA numbers. First load will also |
| include model download and browser cache population time. |
|
|
| ## Example Outputs |
|
|
| Default robot prompt, seed `123`, quality/custom WebGPU path: |
|
|
| | 256 | 512 | 1024 | |
| | --- | --- | --- | |
| |  |  |  | |
|
|
| ## Memory Expectations |
|
|
| WebGPU does not expose exact VRAM usage to JavaScript, so the app reports |
| observable browser memory and known tensor/buffer sizes. The warmed custom |
| transformer path accounts for roughly 3.7 GB of loaded GPU/buffer data. Exact |
| 256 and 512 are realistic on an 8 GB WebGPU adapter when browser memory limits |
| allow it. Exact 768 and 1024 are memory-heavy; the 1024 benchmark completed with |
| browser heap around 4.2-4.3 GiB during VAE decode. |
|
|
| ## License |
|
|
| This bundle is derived from upstream FLUX.2 Klein 4B assets. Use and |
| redistribution must comply with the upstream model license and applicable |
| Hugging Face terms. |
|
|
