PixLab Annotate

What PixLab Annotate is

PixLab Annotate is a browser-based image labeler for creating bounding boxes and polygon segmentation labels for machine learning datasets. You can select multiple images from a device folder and move through them sequentially in the browser. Rectangle and polygon tools create annotations, while zoom, drag, full-screen display, snapshots, and an eraser support the labeling workflow. Labels can be named and assigned colors. The tool also keeps annotation history and supports undo and redo. When labeling is complete, it exports structured JSON with annotation coordinates, rectangle geometry, and label metadata for adaptation to a machine learning pipeline. PixLab says source images are processed in the browser rather than transferred to its servers. Annotation state is stored in browser storage and can be resumed in the same browser on the same device; clearing that storage removes saved work. No account is required to load images, create labels, or export annotation data. The web tool is free, with a plan listed as free. PixLab describes it as useful for developers, researchers, ML engineers, dataset preparation, small teams, QA review, and classroom training. PixLab identifies Symisc Systems, SUARL as its maker and says its SaaS business began with PixLab in 2017. Feature and support requests can be made through the PixLab GitHub repository.

Who it suits

PixLab Annotate suits developers, researchers, and ML engineers preparing datasets with bounding boxes or polygon labels. Its browser workflow and JSON export may also fit small teams, QA review, and classroom training.

Getting started

1. Open the PixLab Annotate website in a browser.
2. Select images from a device folder.
3. Create and name labels, then assign colors as needed.
4. Annotate with rectangles or polygons and use the available review tools.
5. Export the structured JSON when finished.
6. Return in the same browser on the same device to resume saved annotation state.

Verdict

Choose PixLab Annotate if you need a free browser tool for bounding boxes or polygon labels and a structured JSON export. Keep the same browser storage on the same device to resume work.