10 Best Text Annotation Tools and Services

Article by Limarc Ambalina | May 31, 2019

From search engines and sentiment analysis to virtual assistants and chatbots, there are numerous areas of research within machine learning that require text annotation tools and services.

In the AI research and development industries, annotated data is gold. Large quantities of high-quality annotated data is a goldmine. There are a variety of text annotation tools and services available that can provide you with the data you need. Some of these services include entity extraction, part-of-speech tagging, sentiment analysis, and more.


What are the Best  Text Annotation Tools and Services?

Read on below to find out which text annotation service or tool best fits your project.


1. Lionbridge AI

One of the veteran companies in the industry, Lionbridge has over 20 years of experience and over 500,000 expert annotators. With a specialization in linguistics, Lionbridge AI’s crowd staff, fluent in 300 different languages, can annotate your text with accuracy and a quick turnaround. The company is a trusted provider of multilingual data annotation services in the natural language processing field. Some of their text annotation services include text extraction, OCR text correction, linguistic feature tagging, linguistic component analysis, semantic search enablement, and much more. Lionbridge AI also offers custom workflows to cater to your project’s specific needs.

2. Scale

Based in San Francisco, Scale is a provider of computer vision and NLP data annotation services. Through a combination of human work and Scale’s platform, the company provides the following text annotation services: OCR transcription, text categorization, and comparison.

3. Appen

With a huge source of crowdworkers from various countries, Appen is a provider of numerous forms of AI training data. In regards to text annotation services, Appen provides sentiment annotation, intent annotation, named entity annotation, and more.

4. Tagtog

Based in Poland, Tagtog is a text annotation tool that can be used to annotate text both automatically or manually. Tagtog supports native PDF annotation and includes pre-trained NER models for automatic text annotation. On top of the Tagtog tool, the company also has a network of expert workers from various fields that can annotate specialized texts.

5. KConnect

One problem many AI researchers and developers face is getting access to AI training data for highly specialized fields. The team at KConnect seeks to help annotators quickly and efficiently classify and annotate medical data. Specifically, KConnect provides semantic annotation, text analysis, and semantic search services for medical information.

6. Clickworker

Based in the United States and Germany, Clickworker is a crowdsourcing company that has a huge workforce able to perform a variety of tasks. Some of their services regarding text annotation are sentiment analysis, and categorization.

7. ParallelDots

ParallelDots is a provider of numerous APIs which can be used for various types of text annotation. Some of their solutions include sentiment analysis, emotion analysis, keyword extractors, and named entity recognition.

8. LightTag

The LightTag text annotation tool is a platform for annotators and companies to label their text data in house. While the starter package is free, each package level rises in cost and has a monthly limited amount of annotations, starting from 1000 annotations a month.

9. Dandelion API

A relatively new startup company based in Italy, Dandelion API provides a variety of automatic text annotation tools. Their tools can be used for entity extraction, sentiment analysis, and text and content classification.

10. Dataturks

With an in-house API for data annotation and thousands of partnered outsourcing companies, Dataturks provides various image annotation and text annotation services. Some of their text labeling services include text classification, named entity recognition, and part-of-speech labeling.

If you’re in need of text annotation services, get in touch with Lionbridge to find out how our team of 500,000 expert annotators can help. With state-of-the-art text annotation tools, our team can work with you to build custom workflows to match your project’s specific requirements.


Multilingual Text Annotation Services

Lionbridge provides professional text annotation services in over 300 languages.

Some of our most popular languages include:

  • Chinese text annotation
  • Italian text annotation
  • Dutch text annotation
  • Japanese text annotation
  • French text annotation
  • Portuguese text annotation
  • German text annotation
  • Spanish text annotation
Learn how it feels to offload your text annotation tasks
The Author
Limarc Ambalina

Limarc writes content for Lionbridge’s website as part of the marketing team. Born and raised in Canada, Limarc’s love of Japanese pop culture brought him to Japan in 2016 and living in Japan has been his dream come true. Apart from Lionbridge content, you can catch Limarc online writing about anime, video games, and other nerd culture.


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