PDF Buddy documentation

PDF Buddy does the PDF jobs that usually mean uploading a file to a website: merging, splitting, compressing, trimming, redacting, stamping. It does them all in one pass, on your own Mac, and it never changes the file you started with.

Installing

Open the downloaded PDFBuddy.dmg and drag PDF Buddy to your Applications folder. It needs macOS 13 or later, and asks for no system permissions.

Opening documents

Drop PDFs onto the window, or press ⌘O. Drop several and they become one document, in the order they arrived — there is no Merge command because merging is just what dropping does. The + button in the toolbar adds more at any point.

Images are welcome too: drop a PNG, JPEG, HEIC or a screenshot and each becomes a page, centred on US Letter. A photo dragged out of Photos works the same way.

A password-protected PDF asks for its password when it lands. The copy you export won’t be protected unless you ask for that under Output.

Your original file is never modified. PDF Buddy reads it and writes a new document when you save; the save panel suggests a copy’s name so you can’t overwrite the original without meaning to.

Arranging pages

The centre pane has two modes, in the toolbar. Pages puts a thumbnail rail beside the page itself, for reading; Grid shows every page at once, for arranging.

• Reorder by dragging. A gap opens where the page will land. Drag one of several selected pages and they all move, keeping their order.
• Select by clicking, with ⇧-click and ⌘-click for runs and handfuls. The size slider makes the grid’s thumbnails larger or smaller.
• Rotate and delete from the toolbar, the hover controls on a page, or the right-click menu. With nothing selected these act on the whole document — deleting everything asks first.
• ⌘Z undoes any page change, including a drop, and ⇧⌘Z redoes it. Twenty steps deep.

Seeing the result

Double-click a page, or use the magnifier, to see it full size. The Result tab shows that page as the export will actually produce it — the same code writes both, so what you see is what the file will contain. The line beside the tabs says which tasks are affecting the page.

This is the place to check a redaction before a document goes to anyone.

Trim margins

Find the content looks for the ink on each page and cuts the blank paper away from around it. Unlike Preview’s crop, which only sets a box, the discarded margin is genuinely gone from the exported file.

• Margin leaves a little paper around the ink.
• Sensitivity decides how different from the paper a mark has to be before it counts. Scans are speckled and off-white; the paper level is read from each page’s own edge rather than assumed to be white.
• Same crop on every page gives every page of a size the union of what was found, so pages don’t change size as you scroll. Turn it off to cut each page to its own content.

Pages whose ink already reaches the edges, and pages too empty to trim sensibly, are left alone. By hand sets fixed insets instead, in points, millimetres or inches.

Redact

Tick what to look for — emails, social security numbers, phone numbers, card numbers, IP addresses, faces — and add any terms of your own, one per paragraph, for names and case numbers.

What redaction means here: a black rectangle drawn over a PDF hides nothing, because the text is still in the file and still selectable. So a redacted page is rendered to an image and the hidden content is destroyed, not covered. Form fields and markup are flattened before detection, because a form field is exactly where a social security number lives.

Detection runs on your Mac using Apple’s Vision framework, whatever resolution you are exporting at. It is good, and it is not perfect — check the Result tab before you send anything.

Make searchable

Reads the text on scanned pages and lays it into the file invisibly, so the document can be searched and copied from afterwards. Pages that already have a text layer are skipped, so this costs nothing on a document that is half scan and half text.

Numbers and stamps

Page numbers come in four styles, with a starting number and an option to skip the first page. Pick the corner on the position grid.

Bates numbering adds a prefix, a padded number and a suffix — the sequential stamp used in legal production. The difference from page numbers is what happens when you split: page numbers restart in each file, Bates numbers keep counting across all of them.

Header & footer gives you six slots. Type into one after picking it on the grid. {page}, {pages}, {bates}, {file}, {date} and {time} are filled in per page.

Watermark

Text or an image, at an angle, at whatever opacity reads without drowning the page. Tile it across the page or anchor it to one of nine positions. An image mark is sized as a share of the page’s width rather than in pixels, so it lands the same on every page size; PDF logos stay vector-sharp.

Pages per sheet

Two, four, six, eight, nine or sixteen pages arranged on each sheet, filled across or down, with a margin, a gap and optional outlines. Every other task still applies — the pages are trimmed, compressed and stamped on their way onto the sheet — and page numbers count sheets, not pages.

Interleave and reverse

These two act on the document straight away rather than waiting for export, which is why they are buttons rather than switches. ⌘Z undoes them.

Interleave is for a scanner without a duplexer: scan all the fronts, turn the stack over, scan all the backs, and weave the two together. The second pass comes out backwards — flipping a stack does that — so reversing it is the default. The dialog draws both arrangements so you can see which one matches what your scanner did.

Reverse puts the pages back to front, for the feeder that takes a stack face-down.

Compress

Under Output, choose Light, Balanced, Strong or Custom. PDF Buddy picks how to do the work from what the document actually contains:

• A document with real text has its pictures re-encoded in place. Text and line art are untouched, so the page stays sharp, selectable and searchable.
• A pure scan is re-sampled outright, which goes further and costs nothing you can see.
• A document with no pictures at all is left alone, because turning a page of text into an image makes the file bigger — several times bigger.

Drop color takes the color off pages that are being re-sampled anyway; on a color scan that is roughly a third of the size. It isn’t needed for printing — every print dialog can do black and white without touching the file.

The size readout above the Save button shows what you have now and what you will get, before you commit to it.

Split

One file is the default. The alternatives:

• One file per original — the batch mode. Drop forty invoices, stamp them all, and get forty stamped invoices back, each keeping its own name.
• One file per page, or every N pages.
• Custom ranges like 1-3, 7, 10-12, one file per group. 5- means page five to the end.

Output ▸ Pages ▸ Selected narrows the export to the pages ticked in the grid, which composes with any of the above.

Other formats

Export to PNG or JPEG at a resolution you choose, one file per page. Or to Text, or CSV for tables: a page with a real text layer is read exactly, and a scan goes through recognition. Columns are aligned page-wide, so a row with a missing cell keeps the gap instead of shifting every later value one column left.

Passwords and flattening

Protect with a password encrypts the exported PDF. Flatten pages to images turns every page into a picture — the smallest files, at the cost of crisp text, though the words are carried across invisibly so search still works. It shows as locked on when Redact or Drop color needs it, since neither can work on a page that stays a page.

Strip live data, in the task list, leaves form values and markup out of the export altogether. With it off they are painted into the page instead, so they still show but can no longer be edited. It only appears when the document actually has some.

Keep title and author carries the original’s document info across. Off by default, since a copy going to someone else usually shouldn’t.

Keyboard

• ⌘O — open files
• ⌘Z / ⇧⌘Z — undo and redo a page change
• ← / → — previous and next page in the full-size viewer
• Esc — close the viewer

Privacy

Nothing you open is uploaded anywhere, and there is no analytics or telemetry of any kind. Redaction and text recognition run on your Mac. The full policy is on the privacy page.

Updates

PDF Buddy checks bendansby.com for new versions and can install them itself. PDF Buddy ▸ Check for Updates… asks immediately.

Licensing

PDF Buddy is free to try, and the trial holds nothing back — no watermark on your exports, no disabled tasks, no truncated files. That is deliberate: this is usually the last step before a document goes to someone else, and a tool that quietly damages it would be worse than useless. After a week, a reminder appears every few exports until a license is added under PDF Buddy ▸ License.