Combine screenshots into a PDF

One document, one page per capture

Open Images to PDF, add every screenshot at once, and drag the thumbnails into the order you want. It takes PNG and JPG, and it reads the format from the file's own bytes rather than its extension, so a capture saved with the wrong suffix still works. The PNG to PDF page covers this case and points at the same tool until its own preset ships.

Screenshots are almost always PNG, which is the right format for them: it stores text and flat colour without the smearing that JPEG puts around sharp edges. Do not convert them to JPEG first to save space.

Transparent pixels stay transparent

A PNG with an alpha channel keeps it. The alpha is stored as a soft mask on the embedded image rather than being filled in with a colour, so a capture with rounded corners or a drop shadow keeps them instead of gaining black or white boxes.

The transparent parts show the page beneath, which is blank. If you need a specific colour behind a transparent capture, put it there in an image editor before you build the PDF, because the tool adds nothing of its own.

Choosing the page size

Match makes each page exactly the size of its screenshot. A tall phone capture becomes a tall narrow page and a wide monitor capture becomes a wide short page, so the document has pages of different shapes. On screen that is fine and nothing is scaled.

A4 or Letter puts every capture on the same sheet, scaled to fit and centred, and a landscape capture turns the page landscape rather than shrinking into a portrait sheet. Choose this for anything that gets printed, filed or read as a document.

Margins are none, narrow at a quarter inch, or standard at half an inch. None suits a set of captures that should read edge to edge. Standard suits a report.

Keeping the captures readable

Nothing is resampled at any setting, so the pixels you captured are the pixels in the PDF. What changes readability is scaling: a 3840 pixel wide capture squeezed onto an A4 page has small text, whatever the underlying resolution.

Crop before you build the file rather than after. A screenshot cut down to the part that matters reads better at any page size than a full desktop capture with one dialog in the corner.

Order and afterwards

Screenshot file names carry timestamps, which sort correctly by luck rather than by design, and anything you renamed by hand will not. Set the order in the tool and check the thumbnails before building.

If the finished PDF is too large for mail, compress it as a separate step. The image combining guide covers the general case, and the merge hub lists the rest of the cluster.

Why a screen capture makes such a large page

A capture from a high density display holds several pixels for every point of screen space. A phone screenshot can be three pixels wide for each point, so the file is far bigger than the area it showed.

When the page size is set to match, the page is built from the pixel count at 96 pixels to the inch, which makes each point of page space three quarters of a pixel. A tall phone capture therefore becomes a page much larger than a sheet of paper, and it still prints as one sheet because a viewer scales it to fit. If the page dimensions matter to you, choose A4 or Letter and let the capture scale instead.