ksnip

ksnip is a free, open-source screenshot and annotation program for Windows, macOS and Linux. It captures a full screen, a single monitor, a rectangular region, the active window or a freehand area, and then drops the result into an editor tab where the annotation is expected to happen. That editor is the reason people choose ksnip over a system screenshot key: rectangles, ellipses, arrows, freehand lines, text, numbered markers, highlighters, blur and pixelate brushes, crop and scale are all available before the image is saved or shared. Several captures can sit in tabs at once, each with its own undo history.

What it does

After capture, the image opens in an editor with a tool strip on the left and settings on the right. Annotations are layered objects, so a text label can be moved or deleted after the arrow beneath it was drawn. Saving produces PNG, JPEG or BMP with a configurable default name pattern, and the clipboard can be filled automatically. Upload targets send the finished image to a configured destination, and the command-line interface can take a screenshot with a given delay and save it directly to a path for scripting or scheduled tasks.

The workflow

Set a global hotkey for the region capture you use most, take the shot, then annotate immediately while the context is fresh: crop to the relevant part, draw an arrow at the problem, add a numbered marker for each step, blur any personal data, and save with a dated filename. For documentation work, keep several captures open as tabs and finish them as a set. For automated flows, call the executable from a script with a save path so screenshots land in the right archive folder without manual steps.

Practical settings and limits

Configure the screenshot folder, filename pattern, default save format and a few global hotkeys before the first real use; the defaults are sensible but generic. The editor works on a flattened raster canvas in older builds, so very large captures use more memory, and blur and pixelate are applied to the saved pixels with no way to recover the original after saving. Upload targets must be configured with credentials the user supplies, and some platforms restrict global hotkeys under certain desktop environments. Very long scrolling pages are outside the scope of a screen-capture tool.

Who should choose something else

Users who want scrolling capture, integrated video recording or a large built-in sharing service will prefer a heavier suite. Anyone whose operating system already ships an adequate snipping tool may not need a second utility. ksnip suits people who want a scriptable, licence-clean screenshot tool with genuinely usable annotation and no cloud dependency.