RunLocalTools

Image Annotator — Draw, Label & Mark Up Screenshots Free

Annotate screenshots and photos in your browser — pen, arrows, shapes, text labels, numbered steps, and a blur tool for hiding sensitive details. Undo/redo, no account, nothing uploaded.

What it does

Load an image and mark it up: freehand pen, straight lines and arrows, boxes and circles (outlined or filled), text labels, numbered step markers for tutorials, and a blur/pixelate tool for blanking out anything you don’t want visible. Full undo/redo, and you can move or delete anything you’ve drawn before exporting.

How it works

The image is drawn onto a <canvas> at its full native resolution, and every mark you make — a pen stroke, an arrow, a text box — is stored as a small object (its shape, position, and color) rather than baked in immediately, which is what makes undo/redo and moving shapes around possible. Each change is checkpointed onto a history stack (up to 50 steps back), so Ctrl/Cmd+Z always has somewhere to go. The whole canvas, plus your in-progress annotations, are saved to this browser as you work, so a refresh restores exactly where you left off.

The blur tool works by sampling the region you’ve boxed, shrinking it down to a fraction of its size, then drawing it back up without smoothing — the classic pixelation technique — rather than a true Gaussian blur, because it’s fast, has no external dependencies, and reads unambiguously as “this was intentionally obscured” rather than looking like a lens artifact.

How to use it

  1. Drop, click, or paste an image (Ctrl/Cmd+V).
  2. Pick a tool from the sidebar: pen, marker/highlighter, line, arrow, box, circle, text, step number, or blur.
  3. Choose a color and stroke width, and for boxes/circles, whether you want them filled or outlined.
  4. Draw directly on the image. Click once with the text tool to type a label; click once with the step tool to drop the next numbered marker automatically.
  5. Switch to Select to click a shape and drag it, or delete it with the Delete selected button (or the Delete/Backspace key).
  6. Use Undo/Redo freely, then click Preview & download and pick your format.

If you need to permanently strip identifying metadata from a photo rather than just blur part of it, the privacy redaction tool is built specifically for that. Need to crop the image down first? Use crop before annotating. Want your logo on the finished markup? Send it to watermark once you’re done — the “Send to” button under the canvas does this in one click for any shipped tool that accepts images.

FAQ

Is the blur tool a real privacy redaction, or can it be reversed? It permanently overwrites those pixels when you export — the pixelated block is baked into the downloaded image, not a reversible visual filter. That said, if you need audited, purpose-built redaction (metadata stripping included), the dedicated redaction tool is the safer choice for genuinely sensitive material.

Can I move a shape after I’ve drawn it? Yes — switch to the Select tool, click the shape, and drag it. Its color, size, and stroke width stay the same; only its position changes.

What happens if I undo past my last saved point? Undo/redo only affects what’s currently on screen — it doesn’t touch the autosaved copy until you make a change (draw, delete, undo, or redo), at which point the new state is what gets saved.

Does the step-number tool renumber automatically if I delete an earlier step? No — deleting step 2 out of a five-step sequence leaves 1, 3, 4, 5 rather than renumbering everything, so any explanation text you’ve already written referencing “step 4” still points at the same marker.

Will my annotations survive closing the tab? Yes, as long as you don’t clear your browser’s site data — the image and every shape you’ve drawn are saved locally and restored the next time you open the tool, with an option to clear that saved state if you’d rather it not persist.

Privacy

Your image and annotations are stored only in your own browser (via IndexedDB) — never uploaded. That local storage is exactly why the blur tool exists here: if a screenshot has something sensitive in it, you can black it out before it ever needs to leave your device as a finished export.