Why Appen?

Through our years of experience improving search algorithms for clients worldwide, we’ve developed a strong and repeatable methodology for search relevance projects. And with access to an experienced crowd of over 1 million people worldwide, we can quickly scale to meet our customers’ needs.

Our data services


  • Consultative Services

    We work closely with your team to develop a customized program that addresses your unique business challenges.

  • Data Annotation

    Improve your machine learning-based products with high-quality, human-annotated training data.

  • Personalization

    Train your algorithm to deliver more personalized results for your users, driving higher satisfaction and engagement.

  • Relevant Search Evaluation

    We provide customized programs designed to improve the accuracy and relevancy of your search results.

  • Semantic Annotation

    Improve product listings and on site search with semantic annotation.

  • Translation and Localization

    Traditional translation and machine translation services from language and data experts.

Additional resources


Hand pointing at a laptop screen

Why Human-Annotated Data is Key to Machine Learning: Three Use Cases

Machine learning requires high volumes of data for training, validation, and testing. A machine learning model learns to find patterns in the input that is fed to it. This input is referred to as training data. As you train your solution to form relationships between variables, it’s important to have the right data, structured in the right format, covering all …