rembg

What rembg is

rembg is a tool for removing image backgrounds, with several ways to use it in image-processing workflows. It can run as a command-line tool, Python library, HTTP server, or Docker container, and it provides API access and batch processing. The command line supports single images, folders, watch mode, and RGB24 streams. PNG is the listed export format, and replacement backgrounds are not supported.

Available models cover general images, portraits, clothing, anime, and object segmentation; bria-rmbg is the default local model. Edge refinement options include color decontamination, alpha matting, and ViTMatte. Documentation covers use with FFmpeg RGB24 output, OpenCV, PIL, NumPy, Docker, and the HTTP API. Installation instructions cover CPU, NVIDIA CUDA GPU, and AMD ROCm backends. Python versions >=3.11 and <3.14 are listed as requirements. Local ONNX models download on first use and are stored in the rembg models directory. The optional withoutBG backend sends images to withoutBG servers and has a documented maximum upload size of 20 MB. rembg is free and MIT-licensed, though model weights have separate licenses; commercial use of RMBG-2.0 under the BRIA license requires a paid agreement.

Who it suits

rembg suits developers and image-processing workflows that need local background removal, batch processing, or an API. It can also suit users working with Python, Docker, FFmpeg, OpenCV, PIL, or NumPy, provided they account for model-specific licensing when using weights commercially.

Limits

The optional withoutBG backend has a maximum upload size of 20 MB. Commercial use of RMBG-2.0 under the BRIA license requires a paid agreement; model weights have separate licenses.

Getting started

1. Install rembg for a Python version >=3.11 and <3.14.
2. Choose a CPU, NVIDIA CUDA GPU, or AMD ROCm installation backend.
3. Use it through the command line, Python library, HTTP server, or Docker container.
4. Process an image or batch folder and select a suitable model and edge-refinement options.
5. For the optional withoutBG backend, send images to its servers within the 20 MB maximum upload size.

Verdict

Choose rembg if you want a free, flexible background-removal tool with command-line, library, API, and container options. Look elsewhere if you need replacement backgrounds or a different export format, and review model licenses before commercial use.