Mesurer - Inspect, annotate, and give feedback on any live interface

Mesurer runs directly where you build. Share feedback with your agents and your team.

# Build precise software with your coding agent Inspect, measure, annotate, and give feedback on any live interface. Mesurer runs directly where you build. Share precise visual feedback with your agents and team. ## Measure - Measure element dimensions, spacing, padding, and margins - Add configurable column, row, and pixel layout guides - Customize guide colors, opacity, size, gutters, offsets, and alignment - Show pixel rulers and create guides from rulers - Hold Option / Alt to inspect distances between elements and guides - Press Option + S / Alt + S to pin the current distance - Persist guides, measurements, and workspace state across reloads and navigation ## Inspect - Pick and copy rendered colors - Inspect typography and text styles - Reveal page structure with X-ray mode - Inspect elements inside iframes and Shadow DOM - Inspect transparent and nested interface elements - Copy selectors, dimensions, and layout details - Preserve inspection context while switching tools and pages ## Annotate - Add comments pinned to live elements - Reply to, edit, move, resolve, reopen, and search comments - Copy structured feedback for agents - Draw snapping arrows and freehand pen strokes - Add, edit, resize, rotate, and style text annotations - Select and transform multiple annotations together - Undo and redo annotation changes - Keep annotations attached to the page where they were created ## Capture - Capture any part of the visible interface - Include Mesurer overlays in screenshots - Copy or download screenshots instantly - Share precise visual context with your agents and team - Process screenshots locally in the browser ## Designed for the browser - Drag and reposition the toolbar from tools, tabs, Settings, and menus - Minimize and restore Mesurer without losing your workspace - Switch between light and dark themes - Keep controls isolated from host-page styles - Preserve host-page focus, keyboard shortcuts, and interactions - Restore Mesurer across reloads, SPA navigation, and full-page navigation ## Built for visual feedback Mesurer adds a precise visual layer directly to the browser, making it easier to inspect interfaces, communicate changes, and explain exactly what you see. Useful for design engineering, frontend development, UI inspection, visual QA, and agent-assisted development. ## Open source and private by default - Free and open source - No account required - Your page content stays in your browser - Workspace data is stored locally - Screenshots are processed locally - No remote code - No personal data collection