Free tool to mark points and polygon regions

Name: Free tool to mark points and polygon regions
Availability: InStock
Author: magikMaker

by magikMaker·May 6, 2026·21 points·7 comments

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AI Analysis

●MidSolve My ProblemSlick

Solid image annotation tool, but LabelImg and CVAT already do this for free.

Strengths

•Runs entirely client-side with no server uploads for privacy.
•Supports Bezier curves and multiple coordinate origin options.
•Clean UI with undo/redo and keyboard shortcuts for precision.

Weaknesses

•Competes with established free tools like LabelImg and CVAT.
•No unique features that differentiate it from existing annotation software.

Post Description

For a game I'm developing I needed an easy way to create hotspot areas on images. So I hacked together a small tool to do so and before I knew it, I had created an entire app :-)

It allows you to generate JSON or YAML from the coordinates you tack on the image. tack runs entirely in your browser, there is no server side component to it, so good in terms of privacy.

I wrote a blog post about it here: https://bjornwikkeling.com/posts/2026050401-tack-pics-mark-c...

And you can try the tool here: https://tack.pics