PDF Combinerv1.0.0

This tool merges PDFs and images into one PDF entirely inside your browser. Nothing is uploaded, which is the whole point for scanned contracts, medical paperwork, receipts, and anything else you would rather not hand to a web service. Drop files onto the drop zone or pick them with the file button. PDFs, JPGs, PNGs, GIFs, and WEBP files are accepted, up to 50 MB each and 300 MB across the session.

Every page of every PDF you add becomes its own entry in the Pages list, not one entry for the whole file. A twelve page PDF arrives as twelve rows. That is what makes the reordering useful: you can pull page nine of a scanned contract out, drop a photo in behind it, and delete the blank cover sheet the scanner added, all before anything is written. Images arrive as one page each.

A small plus sign sits before every row and after the last one. Opening one gives two choices: insert files at that point, or insert a blank page there. This is how a signature page goes between clauses four and five without being appended to the end and dragged back up thirty rows. Files inserted at a point arrive in their own order starting at that point, so a ten page PDF dropped in at row three becomes rows three through twelve.

Reorder by dragging a row, or use the Up and Down buttons, which sit in their own column on the right of each row and work from the keyboard. Rotate Left, Rotate Right, and Delete sit under the page's own measurements, because they change that page rather than its position. Rotation turns in 90 degree steps and the thumbnail turns with it, showing the page shape you will actually get. Tick the checkboxes to select several pages and use Rotate Selected Left, Rotate Selected Right, or Delete Selected to act on all of them at once. Shift-click a checkbox to select a range.

The Order control sorts the whole list by file name, A to Z or Z to A, as an alternative to arranging it by hand. Sorting is by the file a page came from and then by its position inside that file, so a PDF's own pages never interleave with another file's, and scan-2 sorts before scan-10 rather than after it. A name sort stays on: files added later take their place in that order instead of landing at the end. Moving a row by hand, or using a plus sign, returns the list to a custom order, because a control claiming an order the list no longer holds is worse than no control.

Undo and Redo cover every structural change, including deletes and sorts: Control or Command plus Z and Y from anywhere on the page, and while the focus sits inside the page list, Delete removes the selected pages and R turns them right, or Shift and R left. Those two only act inside the list, so typing elsewhere never deletes anything. After a delete the keyboard lands on the row that took the deleted one's place, so working down a list does not send you back to the top. Clear All is the one action that cannot be undone, because it also forgets the loaded files and resets the settings; it asks before it runs. While a batch is being read or a file written, everything that would change the list is held until the job finishes.

Page sizing has three modes and the differences are real, not cosmetic.

• Keep original, the default, works page by page. PDF pages are copied exactly as they were, byte for byte, with their own page size, rotation, text, and vectors untouched. Image pages get a page sized to the image's own aspect ratio at 8.5 inches wide. The combined file will have mixed page sizes, which is correct when fidelity matters more than uniformity, and it is the only mode that guarantees a source page reaches the output unaltered.
• Fit to Letter puts every page on an 8.5 by 11 inch sheet. Images are scaled down or up to fit inside the sheet, keeping their aspect ratio, and centered, so nothing is cropped or stretched. PDF pages are rescaled the same way: the page content is scaled by a single factor and recentered, so an A4 page arrives as a Letter page with the content intact and slightly smaller.
• Fit to Legal does the same on an 8.5 by 14 inch sheet, which is the size US courts, contracts, and many filing systems expect. A Letter page fitted to Legal keeps its width and gains margin above and below rather than growing.

The sizing arithmetic is open so you can check it or reuse it. Letter is 612 by 792 points and Legal is 612 by 1008 points, at 72 points to the inch. For an unrotated page, scale is min(sheet width divided by page width, sheet height divided by page height), and the drawn size is the original size times that scale, positioned at ((sheet width minus drawn width) divided by 2, (sheet height minus drawn height) divided by 2). For a page turned 90 or 270 degrees the rotated bounding box is what has to fit, so the width and height swap places in both the scale and the centering. Keep original replaces the sheet height with width times original height divided by original width for image pages, and skips the calculation entirely for PDF pages.

Each image row reports its effective DPI: the pixel width of the image divided by the width it will occupy on the finished page in inches. A 1200 pixel wide photo covering 8.5 inches lands at about 141 DPI. Anything under 150 DPI is marked in amber and anything under 96 DPI in red, because that is the point where print output starts to look soft. Switching sizing mode, or rotating a page, changes the number, since both change how much paper the image has to cover.

By default every page keeps the resolution it arrived with. An ordinary RGB JPEG or PNG is embedded with its original bytes at full resolution and is not touched at all. A PDF page in Keep original is copied without being re-encoded, so its text stays text, its vectors stay vectors, and any photograph inside it keeps the resolution it was saved at. In Fit to Letter or Fit to Legal a PDF page is scaled rather than resampled, so it still loses no pixels: the same image data is simply drawn across a different amount of paper, which is what changes its effective DPI.

Settings holds an optional cap. Choosing a target of 300, 200, 150, or 96 DPI resamples any image page that would exceed it down to exactly that figure, which is how a folder of 12 megapixel phone photos becomes a file small enough to email. The cap only ever removes pixels: a page already at or below the target is embedded untouched, so nothing is ever enlarged and no detail is invented. The row shows both numbers, for example 96 DPI at output size, capped from 141, and raising the cap again costs nothing because the original file is still in the browser and the next download is written from it.

One limit is worth stating plainly. The cap reaches image pages only. Images already embedded inside a copied PDF page are copied with that page and cannot be resampled here, so a 40 MB scanned PDF stays 40 MB under a 150 DPI cap. The panel says so, the page count says how many of your pages come from a PDF, and the finished file records it in its own document properties, because the file travels and the panel does not.

Generate Preview renders one real output page at a time onto a canvas, at the size, placement, rotation, and letterboxing the download will carry. Step through with First, Previous, Next, and Last. PDF pages are rendered from the actual page content rather than a stand-in, so the preview shows the text and images on the page. The preview refreshes by itself while it is open when you reorder, rotate, delete, or change sizing mode. On a narrow screen, where Preview stacks below the page list rather than sitting beside it, pressing Generate Preview also scrolls the page down to the preview; on a wide screen the preview is already in view and nothing moves.

Combine and Download appears twice, once under the page list and once at the foot of the preview, so the export is in reach at either end of a long document. Both buttons do the same thing. It writes the PDF and saves it with a name that opens with the date and then records the page count, the sizing mode, and any resolution cap, for example 2026-03-14-combined-14-pages-letter-150dpi.pdf. The date is written year first so a folder of exports sorts into date order by name. Your sizing mode, order preference, duplicate setting, and resolution cap are remembered between visits; file contents are never stored. Clear All empties the list, forgets the loaded files, and puts every setting back to its default.

Two things to know about what this version does not do. Password protected PDFs are refused on import with a message naming the file, because their page content cannot be copied without the password; remove the protection first. Animated GIFs contribute their first frame only. Both cases are reported in the file list rather than passing silently.

Three more affect fidelity rather than function. In Fit to Letter and Fit to Legal, PDF page content is rescaled, and link rectangles and form field positions on those pages can end up offset from the text they belong to; Keep original copies pages without touching them and has no such effect. Interactive form fields do not survive a merge in any mode: the field's appearance is copied with the page, but the form itself is not carried across, so a filled form arrives as a picture of a filled form. Images that the PDF format cannot take directly, meaning WEBP, GIF, CMYK JPEGs, and JPEGs carrying an EXIF rotation flag, are re-encoded through the browser canvas and capped at 3300 pixels on the long side, roughly 300 DPI at Letter size.

Combining documents is the kind of job that is trivial once a year and maddening the day you need it, usually because the only free option online wants an upload of the exact file you cannot upload. Working page by page in the browser covers most of what a desktop PDF editor gets used for, without the install or the account.

• Scanned paperwork that came back wrong: A flatbed or phone scan often produces sideways pages, a stray blank, and a page order that follows the feeder rather than the document. Rotate the sideways pages, delete the blanks, drag the rest into order, and export once.
• Expense reports: Photographs of receipts sit at whatever resolution the phone produced. Fit to Letter puts each on its own sheet and the DPI readout says immediately which ones will be unreadable when printed. A 150 DPI cap then brings a folder of phone photos down to a size that clears a mail server without dropping any below the print floor.
• Contracts and signature pages: A countersigned page usually arrives separately and belongs in the middle, not at the end. Open the plus sign between the two clauses it sits between and insert it there directly.
• Legal exhibits and e-filing: Many filing systems require uniform page sizes and a strict exhibit order. Fit to Legal normalizes a mixture of Letter correspondence, A4 forms, and photographs onto the 8.5 by 14 sheet that US courts expect, and the per page list makes the order explicit rather than implied.
• Batches that arrive out of order: A scanner or camera that names files sequentially rarely hands them over in that sequence. Sorting by file name A to Z puts a hundred pages right in one action, and because the sort holds, files added afterwards drop into place instead of piling up at the end.
• Client deliverables: Merge design mockups, screenshots, a brief, and a signed contract into one file. Insert blank pages as section dividers exactly where the sections break, and keep the whole thing on Letter so it prints and pages predictably.
• Academic and training packets: Slides exported as PDF, reading excerpts, and annotated diagrams merge into one handout. Keep original preserves the proportions of tall infographics and charts that a fixed sheet would shrink, and preserves the text of the source PDFs as text.
• Rebuilding a document from its parts: Split pages out of several PDFs by adding the files and deleting everything you do not want. Because each source page is its own row, extraction and merging are the same operation.
• Portfolios and proposal responses: Assemble artwork, process shots, forms, and certifications into the sequence a reviewer asked for, then step through the preview to confirm the flow before sending.
• Confidential material: Medical records, tax documents, and identity paperwork can be combined without leaving the machine, which is the difference between a merge tool being usable for that work and not.

Use Keep original when a PDF page must survive untouched, when the source pages are already the right size, or when an image's own proportions matter more than a consistent sheet. Use Fit to Letter when the file will be printed, filed, or read by someone who expects uniform pages, and Fit to Legal when the recipient or the filing system expects the longer sheet. Reach for the resolution cap when the file has to travel by email rather than by link, and leave it off when the pages will be printed or archived. Preview before exporting either way; the preview is drawn from the same measurements the export uses, so what it shows is what the file will contain.