Layout inspector

Measure anything.
On any site.

Hover any element to instantly see its dimensions, spacing, and alignment. Measure distances between elements with a single keystroke. Runs entirely in your browser — no account, no backend.

LayoutPeek ← drag to bookmarks

Chrome & Firefox: drag LayoutPeek to your bookmarks bar. Safari: use Copy code, then paste the snippet as the URL for a new bookmark.

Inspect anything.
Hover the sample below for a live width × height readout — only inside this preview box.

With the full bookmarklet you also get selection, ruler lines, and spacing overlays. This preview uses the same hover ring as the shipped tool.

Alex Designers Product Designer · San Francisco
Hold Option / Alt, click one block, then hover another to see edge-to-edge gap (px).
Select & measure

Click any element to select it. Width, height, and position shown instantly as you hover.

Distance measurement

Hold Option / Alt to measure the gap between any two elements.

Ruler lines

Place horizontal or vertical lines to check alignment. Hold Option / Alt to measure between lines. Drag to reposition, to delete.

Spacing overlay

See margin, border, and padding as colored layers — like DevTools box model, inline.

01
Add to bookmarks

Drag LayoutPeek above to your bookmarks bar. On Safari, use Copy code, then paste the snippet as the URL for a new bookmark.

02
Activate on any site

Visit any webpage and click the LayoutPeek bookmark. A small toolbar appears in the top-left corner.

03
Select & measure

In select mode (S), hover elements to see their size. Click to select — then hold Option / Alt and hover another element to measure the gap. Add Shift to pin measurements for screenshots.

04
Place ruler lines

Switch to ruler mode (G), choose H or V, and click to place lines. Hold Option / Alt to measure the distance between placed lines of the same direction. Add Shift to pin measurements for screenshots (⌘⇧3 / ⌘⇧4). Press ⌘Z / ⌘⇧Z to undo or redo (Ctrl+Z / Ctrl+Shift+Z on Windows).

05
Exit

Press Esc to exit and remove all LayoutPeek overlays from the page.

Toolbox98

LayoutPeek is part of toolbox98.com — a curated set of design tools. Available there as a bookmarklet at layoutpeek.xyz.

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