COCO Annotator

7.2easy start · #4 of 24
in AI Image Annotation Tools

Free to practise onyes
Free trialnot on record
Well documentedyes
Runs where you workyes

Runs on api, Linux, self-hosted, Web, Windows.

COCO Annotator is ranked #4 of 24 in AI image annotation tools on The Geeks Club. It runs on API, Linux, Self-hosted, Web, Windows. There is a free plan.

COCO Annotator plans and pricing

All plans

MIT-licensed software Free self-hosted · Docker required github.com · 1 Oct 2026

Compared on AI image annotation tools

Free plan: Yes
Annotation types: bounding boxes, polygons, segmentation masks, keypoints, points
AI-assisted labeling: Yes
Export formats: COCO JSON
API access: Yes
Deployment: self-hosted

Best COCO Annotator alternatives

See all 20

Label Studio 0 of 4 in the starter kit Lesson 17.9 Amazon SageMaker Autopilot 0 of 4 in the starter kit Lesson 27.6 Supervisely 0 of 4 in the starter kit Lesson 37.6 CVAT 0 of 4 in the starter kit Lesson 57.2 Roboflow 0 of 4 in the starter kit Lesson 67.2 Prodigy 0 of 4 in the starter kit Lesson 77.0

The record

Purpose: COCO Annotator is a web-based image annotation tool for creating training data for image localization and object detection.
Annotation formats: It directly exports annotations to COCO format and imports datasets already annotated in COCO format.
Annotation features: It supports object segmentation, keypoints, disconnected objects as one instance, multiple labels per image segment, and custom metadata.
Assisted tools: It includes DEXTR, MaskRCNN, Magic Wand, semi-trained model annotation, and Google Images dataset generation.
REST API: The API uses resource-oriented REST URLs, HTTP response codes, and mostly JSON responses, with a Swagger interface at localhost:5000/api.
Authentication: The feature list includes a user authentication system.
Installation: Docker and docker-compose are required because Docker is currently the only supported installation method.
Scaling: The dedicated-server guidance describes centralized datasets and external access for outsourcing, with a recommended basic instance of 2GB RAM and 2 CPU cores.
Transport security: The deployment guide strongly recommends HTTPS because it encrypts communication between the browser and website.
Architecture: The web server uses Flask, Eventlet, and Gunicorn, while long-running requests are passed to workers through RabbitMQ.
Data storage: Docker volumes store database-generated data and are described as compatible with both Linux and Windows containers.
Support: The project invites users to join its Discord community of machine-learning practitioners.
Security posture: The GitHub repository reports that no SECURITY.md security policy is detected and that there are no published security advisories.
Price from: Free

Where it ranks on The Geeks Club

Best AI Image Annotation Tools in 2026#4 of 24

Is COCO Annotator yours?

Claim it for free: prove the domain, then correct facts, plans and screenshots. An editor reviews every change.

Claim it free Promote COCO Annotator

Sources

github.com/jsbroks/coco-annotator· checked 1 Oct 2026
github.com/jsbroks/coco-annotator/wiki/REST-API· checked 1 Oct 2026
github.com/jsbroks/coco-annotator/wiki/Getting-Sta· checked 1 Oct 2026
github.com/jsbroks/coco-annotator/wiki/Implementat· checked 1 Oct 2026
github.com/jsbroks/coco-annotator/security· checked 1 Oct 2026
github.com/jsbroks/coco-annotator/blob/master/LICE· checked 1 Oct 2026