Label Studio

Label Studio is an open-source data labeling tool from HumanSignal. It handles many data types in a single interface, and you can customize the labeling screen with a simple configuration to fit almost any task. Teams use it to annotate data for classification, object detection, transcription and evaluating model outputs. It supports ML-assisted labeling, where a model proposes labels that people confirm or fix. The community edition is free to self-host, and HumanSignal offers paid enterprise features and a cloud version. It is a good choice for teams that want flexibility without a big bill.