Tablet or desktop required
Tack works best on a bigger screen.
Marking pixel-precise points and pulling bezier handles needs more room than a phone gives. Open tack.pics on a tablet or desktop browser to use the tool.
Read on for what Tack is and what it's for.
Mark · Trace · Export
Tack it down.
A precision tool for marking points and polygon regions on images. Free, runs entirely in your browser — your images never leave your device.
What is Tack?
Pin coordinates onto any image — drop in, click out, copy the data.
Tack is built for game developers, level designers, UI engineers, ML data labelers, and anyone who needs to translate a picture into a structured set of coordinates. Drop in an image, click to drop points, drag to draw bezier curves, and export clean JSON or YAML you can paste straight into your code.
Choose where the origin sits — top-left for screen space, bottom-left for math space, or center for symmetric layouts. Flip the Y-axis if you're working with math coordinates. Switch to normalized 0–1 output if you need resolution-independent data.
Features
Built for precision work.
Points & polygons
Drop single points, draw open polylines, or close shapes into polygons. Mix all three on the same image.
Bezier curves
Click-and-drag to add smooth anchors with handles. Break symmetry with Alt; re-sync with Shift.
Multiple origins
Top-left, top-right, bottom-left, bottom-right, center, or any custom point you click.
Pixel or normalized
Switch between absolute pixels and 0-1 normalized coordinates with one toggle.
Y-axis flip
Match screen-space (Y down) or math-space (Y up) without re-mapping anything yourself.
Round-trip JSON
Load existing JSON back into the tool to edit it. No re-tracing from scratch.
Undo / redo
100 steps of history. Cmd+Z and Cmd+Shift+Z, exactly as you'd expect.
Keyboard nudging
Arrow keys nudge selected anchors by 1 pixel. Hold Shift for 10-pixel jumps.
Works offline
Install as a PWA. The app runs without a network connection once visited.
Use cases
What people use Tack for.
- 2D game collision boundaries
- Hit zones for click / tap targets
- Pathing waypoints for AI
- Spawn points and triggers
- Hotspots for interactive maps
- Annotation regions for ML datasets
- Image-based UI layout coordinates
- Sprite anchor points
- Region-of-interest extraction
- Floorplan / blueprint markup
Privacy
Your images never leave your device.
Tack runs entirely in your browser. The image you load, the points you draw, the JSON you export — none of it is uploaded anywhere. There is no server-side processing, no account, no login. We only collect anonymous, cookie-less page-view analytics so we know the site is reaching people. Read the privacy statement and terms of service.