Widely-used open-source tool for labeling and annotating data across images, text, audio, video, and time-series, with a standardized export format for training and fine-tuning. ML backends can pre-label data to speed up human review, and it increasingly doubles as a human-in-the-loop AI evaluation surface. Maintained by HumanSignal, which offers a hosted Starter tier and Label Studio Enterprise.
LA
Data Ops · HumanSignal
Label Studio
Open-source multi-type data labeling and AI evaluation.
FREEMIUMOpen coreHybridWeb
Model support
Model-agnostic
Where it runs
- Web
Tags
- #data-labeling
- #open-source
- #annotation
- #human-in-the-loop
- #training-data
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