CAD-style markup for drawings and documents: lines, arrows, dimensions, shapes and text, with a magnet that snaps to the lines already inside your PDF.
Tools, shapes, colours, page thumbnails and layers all sit in one left sidebar, so the drawing keeps the full width of the stage.
Everything is drawn as vector and merged back into the original PDF, so it stays sharp at any zoom or print size, with labels that remain selectable, searchable text.
Drag A to B, pull the dimension line out, then type the value and unit. Extension lines, arrowheads and label, done properly. Figures are always typed by hand. The program never invents a measurement from the drawing.
Snaps to annotation corners, to any point along an edge, and, unusually, to the dark lines of the underlying drawing. Start a dimension exactly on a wall, not near it. The crosshair sits on the snapped point, so you see where the click lands before you press.
Plus rectangle, rounded, ellipse, triangle, cloud and polygon, each with its own stroke colour, fill colour and 5 to 100% opacity, so a blue outline over light yellow shading keeps the drawing underneath readable.
Helvetica, Times or Courier, in any combination of bold, italic and underline, on notes, dimension labels and area labels. Restyle something already placed by selecting it first. All three are typefaces a PDF carries without embedding a font file, so the exported labels stay selectable, searchable text rather than a picture of text.
Select one or many: shift-click, Ctrl+A, or sweep a box (blue catches what is fully inside, green catches whatever it touches). Drag the blue points to reshape, hold Shift to lock straight, reorder in the Layers panel, copy and paste between pages.
A scrollable thumbnail strip marks every page that already carries annotations. Thumbnails render in the background, whatever you scroll to gets drawn first, so a hundred-page drawing set opens instantly.
Save Project writes a small .json of annotations and leaves the original PDF untouched. Export PDF shows a confirmation first, listing the source file, the annotation count and which pages are marked, and only then writes the merged file.
Most free online PDF editors upload your file to somebody's server. This one
cannot, even if it wanted to. The page ships with a Content-Security-Policy of
connect-src 'none', which means the browser itself refuses to let it
open a network connection.
Check it yourself: press F12, open the Network tab, and use the app all day. It stays empty. DevTools is left working and console errors are not suppressed, precisely so the claim stays testable.
Esc always finishes what you are drawing and returns to Select. It never throws the work away.
Version 1.50.9 MBChrome or EdgeWindows, macOS, Linux
Launch without downloading DownloadTo carry on editing later, use "Save Project" and keep the .json next to the PDF. Open the original PDF first, then "Open Project". Served over https the editor is faster than double-clicking the file, because pdf.js can start its real background worker.