What Is Image Annotator?

Image Annotator is a browser-based tool for adding visual annotations to images. Whether you're documenting bugs, creating tutorials, or marking up design feedback, this tool gives you everything you need to communicate clearly through images.

Upload any image and use a full set of annotation tools including arrows, shapes, text, highlights, blur areas, and numbered markers. Every annotation can be repositioned, recolored, and resized after placement.

Who Is This For?

Developers & QA - Mark up screenshots for bug reports with arrows, highlights, and numbered steps
Designers - Add feedback annotations directly on design mockups
Content creators - Create annotated screenshots for tutorials and documentation
Anyone - Quick image markup without installing desktop software

Your Data Stays Private

All processing happens in your browser:

No uploads - Images never leave your device
No tracking - We don't collect usage data
No account needed - Start annotating instantly

100% Client-Side Processing: Your images are processed entirely in your browser with zero server uploads, ensuring complete privacy and security for sensitive content.

How to Use Image Annotator

Get started with image annotation in five simple steps. The intuitive interface makes it easy to create professional annotated images in minutes.

Upload an Image

Click the upload area, drag and drop an image, or press Ctrl+V to paste from clipboard. Supported formats include PNG, JPG, WebP, GIF, and BMP.

Choose a Tool

Select a tool from the left toolbar or use keyboard shortcuts:

Arrow (A) - Draw arrows with single or double-headed styles
Line (L) - Draw straight lines
Rectangle (R) - Draw rectangles with optional fill
Ellipse (E) - Draw ellipses with optional fill
Freehand (P) - Draw freely with a pen tool
Text (T) - Add text labels with customizable bold and background
Highlight (H) - Draw semi-transparent highlight overlays
Blur (B) - Pixelate areas to hide sensitive content
Number (N) - Place auto-incrementing numbered markers

Customize

Use the options bar at the top to adjust colors, stroke width, font size, and tool-specific settings. Click any existing annotation to select it and modify its properties.

Edit Annotations

Click any annotation to select it, then drag to reposition. Double-click text annotations to edit their content. Use Delete or Backspace to remove selected annotations. Press Ctrl+Z to undo and Ctrl+Shift+Z to redo.

Download

Choose your output format (PNG, JPEG, or WebP) and click Download. The image is exported at its original full resolution with all annotations baked in.

Pro Tip: Master keyboard shortcuts to speed up your workflow. Each tool has a single-key shortcut, and common actions like undo (Ctrl+Z) and paste (Ctrl+V) work as expected.

Features

A comprehensive toolkit designed for professional image annotation with intuitive controls and powerful customization options.

Annotation Tools

A complete set of tools for marking up images with precision and clarity:

Arrows & Lines

Point to specific areas or connect elements with precision.

Single or double-headed arrows
Straight lines for boundaries
Customizable stroke width

Shapes

Highlight regions with rectangles and ellipses.

Outline or filled shapes
Perfect for highlighting areas
Adjustable colors and borders

Freehand Drawing

Draw freely with a pen for custom markup.

Natural drawing experience
Variable stroke width
Perfect for custom annotations

Text Labels

Add clear text annotations with full customization.

5 font sizes (14-48px)
Bold weight option
Optional dark background

Highlight

Draw attention with semi-transparent overlays.

Semi-transparent effect
Multiple color options
Perfect for emphasis

Blur Tool

Protect sensitive information with pixelation.

Pixelate sensitive content
Hide emails, names, passwords
Unreadable in exports

Numbered Markers

Create step-by-step instructions effortlessly.

Auto-incrementing numbers
Colored circle backgrounds
Perfect for tutorials

Interactive Editing

Edit and refine annotations with intuitive controls that make adjustments quick and easy:

Click & Drag

Click to select any annotation from any active tool
Drag to move annotations after placement
Double-click text to edit content inline

Live Updates

Live style updates - Change color, stroke, or size on selected annotations
Context-aware options - Options bar shows relevant controls for the selected annotation type

Customization

Fine-tune every aspect of your annotations with comprehensive styling options:

Colors

7 preset colors plus custom color picker

Stroke Width

4 widths: 2, 3, 5, 8 pixels

Font Sizes

5 sizes: 14, 18, 24, 32, 48

Style Options

Fill, bold, background, arrow style toggles

Undo & Redo

Full undo/redo history with up to 50 states. Use Ctrl+Z and Ctrl+Shift+Z or the toolbar buttons to navigate through your editing history.

Never Lose Work: The comprehensive undo system tracks up to 50 editing states, so you can experiment freely and revert any changes instantly.

Export

Download annotated images at their original full resolution. Choose between PNG, JPEG, or WebP output format based on your needs:

PNG - Best for screenshots and images requiring transparency
JPEG - Ideal for photographs with smaller file sizes
WebP - Modern format offering excellent compression with quality

Frequently Asked Questions

What image formats can I upload?

You can upload PNG, JPG, WebP, GIF, and BMP images. You can also paste images directly from your clipboard using Ctrl+V.

Is the exported image the same resolution as the original?

Yes. The canvas displays a scaled-down preview, but when you download, the image is exported at its original full resolution with all annotations rendered at the correct scale.

Can I edit annotations after placing them?

Yes. Click any annotation to select it, then drag to reposition. You can also change its color, stroke width, and other properties from the options bar. Double-click text annotations to edit their content.

How do I hide sensitive information?

Use the Blur (B) tool to draw a rectangle over sensitive areas. The tool pixelates the content underneath, making it unreadable in the exported image.

What keyboard shortcuts are available?

Each tool has a single-key shortcut: V (Select), A (Arrow), L (Line), R (Rectangle), E (Ellipse), P (Freehand), T (Text), H (Highlight), B (Blur), N (Number). Use Ctrl+Z for undo, Ctrl+Shift+Z for redo, and Delete to remove selected annotations.

Are my images uploaded to a server?

No. All image processing happens entirely in your browser. Your images are never uploaded to any server, ensuring complete privacy.

Can I annotate multiple images?

You can work on one image at a time. Click New Image to load a different image. Note that loading a new image will clear existing annotations.

What output formats are available?

You can export annotated images as PNG, JPEG, or WebP. PNG preserves transparency, JPEG is best for photos, and WebP offers good compression with quality.