Best Image Annotation Tools in China of 2025

Ango Hub

iMerit

Ango Hub is a quality-focused, enterprise-ready data annotation platform for AI teams, available on cloud and on-premise. It supports computer vision, medical imaging, NLP, audio, video, and 3D point cloud annotation, powering use cases from autonomous driving and robotics to healthcare AI. Built for AI fine-tuning, RLHF, LLM evaluation, and human-in-the-loop workflows, Ango Hub boosts throughput with automation, model-assisted pre-labeling, and customizable QA while maintaining accuracy. Features include centralized instructions, review pipelines, issue tracking, and consensus across up to 30 annotators. With nearly twenty labeling tools—such as rotated bounding boxes, label relations, nested conditional questions, and table-based labeling—it supports both simple and complex projects. It also enables annotation pipelines for chain-of-thought reasoning and next-gen LLM training and enterprise-grade security with HIPAA compliance, SOC 2 certification, and role-based access controls.

15 Ratings

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Vertex AI

Google

Image Annotation in Vertex AI is a powerful tool for preparing visual data for training computer vision models. By labeling and tagging objects, features, or regions of interest in images, businesses can create more accurate and specialized models for tasks like object detection and facial recognition. Vertex AI provides automated and manual annotation tools that can handle large volumes of image data, ensuring high-quality annotations for machine learning models. New customers receive $300 in free credits, enabling them to test the platform’s image annotation capabilities. With this feature, businesses can accelerate the development of visual AI solutions, increasing the accuracy and reliability of their models.

726 Ratings

Starting Price: Free ($300 in free credits)

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Roboflow

Roboflow has everything you need to build and deploy computer vision models. Connect Roboflow at any step in your pipeline with APIs and SDKs, or use the end-to-end interface to automate the entire process from image to inference. Whether you’re in need of data labeling, model training, or model deployment, Roboflow gives you building blocks to bring custom computer vision solutions to your business.

1 Rating

Starting Price: $250/month

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Clickworker

clickworker is globally the largest open crowd sourcing provider. The company has a huge number of services using a "one to many" approach where your company can use many Clickworkers to achieve the outcome you desire. Most frequently, clickworker provides customized data collection, categorization, evaluation, tagging and annotation services to create AI/ML training data for Data Scientists, and also provides SEO texts, product tags, categories and surveys for online businesses and retailers. clickworker serves most industries and applications using the skills of their 4.0M+ Clickworkers. This crowd gathers data through a wide range of micro-tasks, utilizing a sophisticated crowd-sourcing platform and fully featured mobile app.

1 Rating

Starting Price: $0.03 one-time payment

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SuperAnnotate

SuperAnnotate is the world's leading platform for building the highest quality training datasets for computer vision and NLP. With advanced tooling and QA, ML and automation features, data curation, robust SDK, offline access, and integrated annotation services, we enable machine learning teams to build incredibly accurate datasets and successful ML pipelines 3-5x faster. By bringing our annotation tool and professional annotators together we've built a unified annotation environment, optimized to provide integrated software and services experience that leads to higher quality data and more efficient data pipelines.

1 Rating

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Roora

Roora provides high-quality data annotation services for machine learning, specializing in image, video, and text annotation across various industries such as healthcare, autonomous vehicles, and retail. With expertise in techniques like bounding boxes, semantic segmentation, and object detection, Roora helps businesses enhance AI models for better performance. The platform’s skilled team ensures that data labeling is accurate, scalable, and secure, improving AI systems' ability to recognize and classify visual elements in real-world applications like facial recognition, medical imaging, and autonomous navigation.

1 Rating

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Clarifai

Clarifai is a leading AI platform for modeling image, video, text and audio data at scale. Our platform combines computer vision, natural language processing and audio recognition as building blocks for developing better, faster and stronger AI. We help our customers create innovative solutions for visual search, content moderation, aerial surveillance, visual inspection, intelligent document analysis, and more. The platform comes with the broadest repository of pre-trained, out-of-the-box AI models built with millions of inputs and context. Our models give you a head start; extending your own custom AI models. Clarifai Community builds upon this and offers 1000s of pre-trained models and workflows from Clarifai and other leading AI builders. Users can build and share models with other community members. Founded in 2013 by Matt Zeiler, Ph.D., Clarifai has been recognized by leading analysts, IDC, Forrester and Gartner, as a leading computer vision AI platform. Visit clarifai.com

Starting Price: $0

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Alegion

Alegion is the data labeling solution for enterprise-grade Machine Learning. We lead the industry in streaming, high-resolution, high-density video annotation, delivering accurately-annotated, model-ready data to train and validate ML models. Alegion provides both the platform and workforce to operate with quality at scale, processing structured and unstructured data including video, image, audio, and text. Our ML powered platform speeds up task completion by as much as 70%, including classless object tracking and single click smart polygon generation. Segmentation options include Keypoint, Bounding Box, Polyline, & Polygon segmentation, for image and video. Semantic Segmentation tools deliver seamless entity boundaries with pixel perfect accuracy. NLP and NER capabilities support text and audio classification and sentiment analysis. The platform is highly configurable to support hybrid use cases. Available via SaaS (Alegion Control), Managed Platform, and Managed Labeling Services.

Starting Price: $5000

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Keylabs

Keylabs.ai is an advanced image and video annotation platform designed by experts to provide high-performance data annotation, management features, and unique operations management capabilities. With a proven track record of handling large datasets efficiently and accurately, Keylabs.ai is trusted by global technology leaders. It combines innovative technology with a user-centric design to support projects of any type and scale. The platform supports various image and video annotation dataset formats, including semantic segmentation, cuboid 3D point cloud, polygons, key points, lane annotation, and bitmask. Additionally, Keylabs.ai allows seamless integration of client models to meet specific project requirements. The annotation process is enhanced with exclusive post-annotation tools like Edge Smooth and Healer, ensuring greater precision and efficiency. By simplifying image annotation, Keylabs.ai provides AI developers with a high degree of flexibility to optimize workflow.

Starting Price: $1/hour

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Keymakr

Keymakr specializes in providing image and video data annotation, data creation, data collection, and data validation services for AI/ML Computer Vision projects. With a strong technological foundation and expertise, Keymakr efficiently manages data across various domains. Keymakr's motto, "Human teaching for machine learning," reflects its commitment to the human-in-the-loop approach. The company maintains an in-house team of over 600 highly skilled annotators. Keymakr's goal is to deliver custom datasets that enhance the accuracy and efficiency of ML systems. Our services: - Image annotation - Video annotation - Data validation - Data creation - Data collection - Generative AI - Custom AI

Starting Price: $7/hour

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Prodigy

Explosion

Radically efficient machine teaching. An annotation tool powered by active learning. Prodigy is a scriptable annotation tool so efficient that data scientists can do the annotation themselves, enabling a new level of rapid iteration. Today’s transfer learning technologies mean you can train production-quality models with very few examples. With Prodigy you can take full advantage of modern machine learning by adopting a more agile approach to data collection. You'll move faster, be more independent and ship far more successful projects. Prodigy brings together state-of-the-art insights from machine learning and user experience. With its continuous active learning system, you're only asked to annotate examples the model does not already know the answer to. The web application is powerful, extensible and follows modern UX principles. The secret is very simple: it's designed to help you focus on one decision at a time and keep you clicking – like Tinder for data.

Starting Price: $490 one-time fee

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V7 Darwin

V7

V7 Darwin is a powerful AI-driven platform for labeling and training data that streamlines the process of annotating images, videos, and other data types. By using AI-assisted tools, V7 Darwin enables faster, more accurate labeling for a variety of use cases such as machine learning model training, object detection, and medical imaging. The platform supports multiple types of annotations, including keypoints, bounding boxes, and segmentation masks. It integrates with various workflows through APIs, SDKs, and custom integrations, making it an ideal solution for businesses seeking high-quality data for their AI projects.

Starting Price: $150

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Diffgram Data Labeling

Diffgram

Your AI Data Platform Quality Training Data for Enterprise Data Labeling Software for Machine Learning Free on your Kubernetes Cluster Up to 3 Users. TRUSTED BY 5,000 HAPPY USERS WORLDWIDE Images, Video, Text Spatial Tools Quadratic Curves, Cuboids, Segmentation, Box, Polygons, Lines, Keypoints, Classification Tags, and More Use the exact spatial tool you need. All tools are easy to use, fully editable, and powerful ways to represent your data. All tools are available in Video. Attribute Tools More Meaning. More degrees of freedom through: Radio buttons. Multiple select. Date pickers. Sliders. Conditional logic. Directional Vectors. And more! You can capture complex knowledge and encode it into your AI. Streaming Data Automation Up to 10x Faster then manual labeling

Starting Price: Free

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SUPA

Supercharge your AI with human expertise. SUPA is here to help you streamline your data at any stage: collection, curation, annotation, model validation and human feedback. Better data, better AI. SUPA is trusted by AI teams to solve their human data needs. Our lightning-fast machine-led labeling platform integrates with our diverse workforce to provide high-quality data at scale, making it the most cost-efficient solution for your AI. We do next-gen labeling for ‍next-gen AI. Our use cases range from LLM generation, data curation, Segment Anything (SAM) output validation to sketch generation and semantic segmentation.

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UBIAI

Leverage UBIAI's powerful labeling platform to train and deploy your custom NLP model faster than ever! When dealing with semi-structured text such as invoices or contracts, preserving document layout is key to training a high-performance model. Combining natural language processing and computer vision, UBIAI’s OCR feature allows you to perform NER, relation extraction, and classification annotation directly on native PDF documents, scanned images or pictures from your phone without losing any layout information, resulting in a significant boost of your NLP model performance. With UBIAI text annotation tool you can perform named entity recognition (NER), relation extraction and document classification all in the same interface. Unlike other tools, UBIAI enables you to create nested and overlapping entities containing multiple relations.

Starting Price: $299 per month

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Label Your Data

Label Your Data stands for exceptional data annotation service. With PCI DSS (level 1) and ISO:27001 certifications, and adherence to GDPR, CCPA, and HIPAA, we guarantee your data is handled securely. Our services cover Automotive, Robotics, Fintech, Healthcare, E-commerce, Manufacturing, and Insurance industries. On a mission to co-build an AI-driven economy, we offer customized solutions for both enterprise and R&D projects with 500+ annotators on board. From Computer Vision and NLP annotation to data processing, Label Your Data delivers accurate and secure results to scale your AI projects.

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makesense.ai

makesense.ai is a free-to-use online tool for labeling photos. Thanks to the use of a browser it does not require any complicated installation, just visit the website and you are ready to go. It also doesn't matter which operating system you're running on, we do our best to be truly cross-platform. It is perfect for small computer vision deep learning projects, making the process of preparing a dataset much easier and faster. Prepared labels can be downloaded in one of the multiple supported formats. The application was written in TypeScript and is based on React/Redux duo.

Starting Price: Free

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Scalabel

Support various types of annotations on both images and videos. A scalable open-source web annotation tool. Support simple “click and drag” actions and options to add multiple attributes. Feature functions to fit boundaries with Bezier curves and copy shared boundaries. Annotate the area that the driver is currently driving on. Annotate lane marking for vision-based vehicle localization and trajectory planing. Accurate and intuitive four-click method to encapsulate objects of interest. Predict annotations between frames using object tracking and interpolation algorithm for bounding boxes. Annotation predictions for object instances. 2D tracking features extended to 3D.

Starting Price: Free

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RectLabel

An offline image annotation tool for object detection and segmentation. Draw polygons, cubic bezier curves, line segments, and points. Draw oriented bounding boxes in aerial images. Draw key points with a skeleton. Draw pixels with brushes and superpixels. Read/write in PASCAL VOC xml and YOLO text formats. Export to CreateML object detection and image classification formats. Export to COCO, Labelme, YOLO, DOTA, and CSV formats. Export indexed color mask images and grayscale mask images. Settings for objects, attributes, hotkeys, and labeling fast. Customize the label dialog to combine with attributes. 1-click buttons speed up selecting the object name. Auto-suggest works for more than 5000 object names. Search object, attribute, and image names in a gallery view. Automatic labeling using Core ML models. Automatic text recognition using OCR. Video to image frames, augment images, etc. Supports English, Chinese, Korean, and 11 other languages.

Starting Price: Free

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Mindkosh

Mindkosh AI

Mindkosh is the data platform for curating, labeling and validating datasets for your AI projects. Our industry leading data annotation platform combines collaborative features with AI-assisted annotation features to provide a comprehensive suite of tools to label any kind of data, be it Images, videos or 3D pointclouds such as those from Lidar. For images, Mindkosh offers semi-automatic segmentation, pre-labeling for bounding boxes and automatic OCR. For videos, automatic interpolation can reduce massive amounts of manual annotation. And for lidar, 1-click annotation allows you to create cuboids in just 1 click! If you are simply looking to get your data labeled, our high quality data annotation services combined with an easy to use Python SDK and web-based review platform, provide an unmatched experience.

Starting Price: $30/user/month

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Dokit

The Dokit manual software empowers you to create, share and track visual step-by-step instructions, user guides and best practices that fit any screen and device. Dokit includes features such as Cataloging/Categorization, collaboration, Page templates, Visual editor, Drag & Drop, Media Gallery, Image annotation, Multilingual, Document importation, Approval workflow, Notifications, Forum and Comments. Alternative competitor software options to Dokit include Dozuki, Swipeguide, Speachme and StepShot

Starting Price: 60€/month

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Supervisely

The leading platform for entire computer vision lifecycle. Iterate from image annotation to accurate neural networks 10x faster. With our best-in-class data labeling tools transform your images / videos / 3d point cloud into high-quality training data. Train your models, track experiments, visualize and continuously improve model predictions, build custom solution within the single environment. Our self-hosted solution guaranties data privacy, powerful customization capabilities, and easy integration into your technology stack. A turnkey solution for Computer Vision: multi-format data annotation & management, quality control at scale and neural networks training in end-to-end platform. Inspired by professional video editing software, created by data scientists for data scientists — the most powerful video labeling tool for machine learning and more.

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Hive Data

Hive

Create training datasets for computer vision models with our fully managed solution. We believe that data labeling is the most important factor in building effective deep learning models. We are committed to being the field's leading data labeling platform and helping companies take full advantage of AI's capabilities. Organize your media with discrete categories. Identify items of interest with one or many bounding boxes. Like bounding boxes, but with additional precision. Annotate objects with accurate width, depth, and height. Classify each pixel of an image. Mark individual points in an image. Annotate straight lines in an image. Measure, yaw, pitch, and roll of an item of interest. Annotate timestamps in video and audio content. Annotate freeform lines in an image.

Starting Price: $25 per 1,000 annotations

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LinkedAI

LinkedAi

We label your data with the higher quality standards to fulfill the needs of the most complex AI projects, using our proprietary labeling platform. Now you can get back to creating the products your customers love. We provide an end-to-end solution for image annotation with fast labeling tools, synthetic data generation, data management, automation features and annotation services on-demand with integrated tooling to accelerate and finish computer vision projects. When every pixel matters, you need accurate, AI-powered intuitive image annotation tools to support your specific use case, including instances, attributes and much more. Our in-house highly trained data labelers are able to deal with any data challenge. As your data labeling needs grow over time, you can count on us to scale the workforce necessary to meet your goals, and in contrast to crowdsourcing platforms your data quality will not suffer.

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Amazon SageMaker Ground Truth

Amazon Web Services

Amazon SageMaker allows you to identify raw data such as images, text files, and videos; add informative labels and generate labeled synthetic data to create high-quality training data sets for your machine learning (ML) models. SageMaker offers two options, Amazon SageMaker Ground Truth Plus and Amazon SageMaker Ground Truth, which give you the flexibility to use an expert workforce to create and manage data labeling workflows on your behalf or manage your own data labeling workflows. data labeling. If you want the flexibility to create and manage your own personal and data labeling workflows, you can use SageMaker Ground Truth. SageMaker Ground Truth is a data labeling service that makes data labeling easy and gives you the option of using human annotators via Amazon Mechanical Turk, third-party providers, or your own private staff.

Starting Price: $0.08 per month

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Labellerr

Labellerr is a data annotation platform designed to expedite the preparation of high-quality labeled datasets for AI and machine learning models. It supports various data types, including images, videos, text, PDFs, and audio, catering to diverse annotation needs. The platform offers automated annotation features, such as model-assisted labeling and active learning, to accelerate the labeling process. Additionally, Labellerr provides advanced analytics and smart quality assurance tools to ensure the accuracy and reliability of annotations. For projects requiring specialized knowledge, Labellerr offers expert-in-the-loop services, including access to professionals in fields like healthcare and automotive.

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CVAT

Annotate better with CVAT, the industry-leading data engine for machine learning. Used and trusted by teams at any scale, for data of any scale. CVAT’s blazing-fast, intuitive user interface, was designed by working closely with real-world teams solving real-world problems. From medical to retail to autonomous vehicles, world’s most ambitious AI teams use CVAT as a part of their AI workflow every day. No matter what your input data or expected results are, CVAT is ready. It works great with images, videos, and even 3D. Bounding boxes, polygons, points, skeletons, cuboids, trajectories, and more. Annotate more efficiently with automated interactive algorithms like intelligent scissors, histogram equalization, and more. Gain actionable insights with metrics such as annotator working hours, objects per hour, and more.

Starting Price: $33 per month

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Label Studio

The most flexible data annotation tool. Quickly installable. Build custom UIs or use pre-built labeling templates. Configurable layouts and templates adapt to your dataset and workflow. Detect objects on images, boxes, polygons, circular, and key points supported. Partition the image into multiple segments. Use ML models to pre-label and optimize the process. Webhooks, Python SDK, and API allow you to authenticate, create projects, import tasks, manage model predictions, and more. Save time by using predictions to assist your labeling process with ML backend integration. Connect to cloud object storage and label data there directly with S3 and GCP. Prepare and manage your dataset in our Data Manager using advanced filters. Support multiple projects, use cases, and data types in one platform. Start typing in the config, and you can quickly preview the labeling interface. At the bottom of the page, you have live serialization updates of what Label Studio expects as an input.

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ImgLab

ImgLab is an open-source tool designed to simplify the task of annotating images for machine learning and artificial intelligence applications. It provides an intuitive interface that enables users to mark up images with metadata, such as bounding boxes, points, lines, or polygons to identify specific features or objects within the image. ImgLab supports multiple annotation formats including COCO, Pascal VOC, and YOLO, facilitating compatibility with a variety of machine learning models and platforms. It's designed to work with large image sets, making it suitable for complex machine learning tasks.

Starting Price: Free

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Encord

Achieve peak model performance with the best data. Create & manage training data for any visual modality, debug models and boost performance, and make foundation models your own. Expert review, QA and QC workflows help you deliver higher quality datasets to your artificial intelligence teams, helping improve model performance. Connect your data and models with Encord's Python SDK and API access to create automated pipelines for continuously training ML models. Improve model accuracy by identifying errors and biases in your data, labels and models.

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Best Image Annotation Tools in China

Compare the Top Image Annotation Tools in China as of August 2025

What are Image Annotation Tools in China?

Ango Hub

Vertex AI

Roboflow

Clickworker

SuperAnnotate

Roora

Clarifai

Alegion

Keylabs

Keymakr

Prodigy

V7 Darwin

Diffgram Data Labeling

SUPA

UBIAI

Label Your Data

makesense.ai

Scalabel

RectLabel

Mindkosh

Dokit

Supervisely

Hive Data

LinkedAI

Amazon SageMaker Ground Truth

Labellerr

CVAT

Label Studio

ImgLab

Encord

Best Image Annotation Tools in China

Compare the Top Image Annotation Tools in China as of August 2025

What are Image Annotation Tools in China?

Ango Hub

Vertex AI

Roboflow

Clickworker

SuperAnnotate

Roora

Clarifai

Alegion

Keylabs

Keymakr

Prodigy

V7 Darwin

Diffgram Data Labeling

SUPA

UBIAI

Label Your Data

makesense.ai

Scalabel

RectLabel

Mindkosh

Dokit

Supervisely

Hive Data

LinkedAI

Amazon SageMaker Ground Truth

Labellerr

CVAT

Label Studio

ImgLab

Encord

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