tack. — Mark coordinates on images

Mark · Trace · Exporttack. 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.JSON / YAML export Bezier polygons Custom origin / units Works offline (PWA)About 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.FeaturesBuilt for precision work.Points & polygonsDrop single points, draw open polylines, or close shapes into polygons. Mix all three on the same image.Bezier curvesClick-and-drag to add smooth anchors with handles. Break symmetry with Alt; re-sync with Shift.Multiple originsTop-left, top-right, bottom-left, bottom-right, center, or any custom point you click.Pixel or normalizedSwitch between absolute pixels and 0-1 normalized coordinates with one toggle.Y-axis flipMatch screen-space (Y down) or math-space (Y up) without re-mapping anything yourself.Round-trip JSONLoad existing JSON back into the tool to edit it. No re-tracing from scratch.Undo / redo100 steps of history. Cmd+Z and Cmd+Shift+Z, exactly as you'd expect.Keyboard nudgingArrow keys nudge selected anchors by 1 pixel. Hold Shift for 10-pixel jumps.Works offlineInstall as a PWA. The app runs without a network connection once visited.Use casesWhat people use Tack for.2D game collision boundariesHit zones for click / tap targetsPathing waypoints for AISpawn points and triggersHotspots for interactive mapsAnnotation regions for ML datasetsImage-based UI layout coordinatesSprite anchor pointsRegion-of-interest extractionFloorplan / blueprint markupPrivacyYour 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.