How to reorder pages in a scanned pdf document
- Step 1Open the scan and number the pages — Open the scanned PDF in any viewer and note the page count and which pages are misplaced. Pages are 1-based — the first page is
1, not0. For a duplex 'fronts then backs' scan, write down which scanned page holds each real page. - Step 2Drop the PDF onto the reorder tool — Drag the scanned file onto the dropzone, or click browse to pick it. One PDF at a time. Parsing happens locally — the page count shows at the top once it loads.
- Step 3Type the correct page order — In the New page order box, enter the page numbers separated by commas, e.g.
1, 3, 2, 4, 5. The output will contain exactly those pages, in that order. Spaces around commas are ignored. - Step 4Include every page you want to keep — Only the page numbers you list end up in the output. If a page isn't in your list, it is dropped. For a full reorder, your list must name all pages — e.g. a 6-page scan needs six numbers.
- Step 5Click Process and review the page count — The result panel shows the input page count and output size. The output page count equals how many numbers you entered — a quick sanity check that you didn't drop or duplicate a page by accident.
- Step 6Download the corrected scan — Click Download to save the rebuilt file (named
<original>.reorder.pdf). The original is never modified, so you can re-drop it and try a different sequence if needed.
Common scan misfeeds and the order to type
Each row shows the wrong order an ADF produced and the exact sequence to enter in the New page order box to fix it. Examples use a small document for clarity; the same pattern scales.
| Misfeed type | What the scan looks like | Order to type |
|---|---|---|
| Two adjacent pages swapped (double-feed) | 1, 2, 4, 3, 5, 6 — pages 3 and 4 came out reversed | 1, 2, 4, 3, 5, 6 (list pages 3 and 4 in the right slots) |
| Duplex: all fronts, then all backs (6-page doc) | Scan order is fronts 1,3,5 then backs 2,4,6, i.e. file pages 1,2,3,4,5,6 map to real 1,3,5,2,4,6 | 1, 4, 2, 5, 3, 6 (interleave to restore 1-6) |
| Jam: last 2 sheets re-fed at the end | 1, 2, 5, 6, 3, 4 — pages 3 and 4 jammed and were re-scanned at the end | 1, 2, 5, 6, 3, 4 (place 3 and 4 back in sequence) |
| Whole stack fed upside-down / reversed | 6, 5, 4, 3, 2, 1 — sheets went in back-to-front | 6, 5, 4, 3, 2, 1 (type the page numbers in descending order) |
| One page misfiled to the front | 5, 1, 2, 3, 4, 6 — page 5 fed first | 2, 3, 4, 5, 1, 6 — wait: name the original page numbers in target order → 1, 2, 3, 4, 5, 6 if 5 was simply first; for a true move, list pages where you want them |
What the tool does with your input
The reorder engine parses the order string by splitting on commas and reading each token as an integer (pdf-processor.ts → reorderPages in pdfEngine.ts).
| Input | Behaviour | Result |
|---|---|---|
1, 3, 2 | Each comma-separated number is read; pages copied in that order | 3-page PDF: page 1, then page 3, then page 2 |
| A page number you omit | Pages not listed are never copied into the output | Omitted pages are dropped — list every page you want to keep |
A page number listed twice (1, 2, 2, 3) | The page is copied each time it appears | That page appears twice in the output |
An out-of-range number (9 in a 5-page doc) or 0 | Numbers outside 1…pageCount are silently filtered out | Ignored — no error, just skipped |
A range like 5-10 | Range syntax is NOT supported here — 5-10 is read as the single number 5 | Only 5 is added. Type each page individually instead |
| Empty box | No valid numbers parsed | Error: 'Enter at least one page number.' |
Cookbook
Real ADF and duplex scan-order fixes, with the exact sequence to type and what the output contains.
Fix two swapped pages from a double-feed
A 6-page contract scanned cleanly except the feeder grabbed pages 3 and 4 together and they came out reversed. You don't need to re-scan — list all six pages with 3 and 4 in the correct slots.
Scanned (wrong): 1 2 4 3 5 6 Type in box: 1, 2, 3, 4, 5, 6 Output (1.reorder.pdf): 1 2 3 4 5 6 Input pages: 6 Output pages: 6
Untangle a duplex 'fronts-then-backs' scan
A simplex-mode duplex scan of a 6-page document produced all three fronts first, then all three backs. The file's physical pages are 1=real1, 2=real3, 3=real5, 4=real2, 5=real4, 6=real6. Interleave them.
File page order: 1 2 3 4 5 6 Holds real page: 1 3 5 2 4 6 Type in box: 1, 4, 2, 5, 3, 6 Output restores: 1 2 3 4 5 6
Move re-fed pages back after a jam
A scanner jammed on pages 3 and 4; you re-fed those two sheets and they were appended to the end of an 8-page batch. The file is now 1,2,5,6,7,8,3,4.
Scanned (wrong): 1 2 5 6 7 8 3 4 Type in box: 1, 2, 3, 4, 5, 6, 7, 8 Output: 1 2 3 4 5 6 7 8 (the re-fed pages 3 and 4 slot back into place)
Reverse a stack fed back-to-front
An entire 10-page stack went into the feeder upside-down, so the scan is in reverse. There is no Reverse button — type the page numbers in descending order.
Scanned (wrong): 10 9 8 7 6 5 4 3 2 1 Type in box: 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 Output: 1 2 3 4 5 6 7 8 9 10
Drop a blank separator page while reordering
Batch scans often insert a blank page between documents. Because only listed pages are kept, you can correct the order AND drop the blank in one pass — just leave the blank's number out of your list.
Scan: 1=cover 2=BLANK 3=body 4=body 5=signature Type in box: 1, 3, 4, 5 Output: cover, body, body, signature (blank page 2 dropped) Input pages: 5 Output pages: 4
Edge cases and what actually happens
A page you didn't list is missing from the output
By designThe tool builds the output from your list only — it copies the pages you name, in the order you name them. Any page whose number you leave out is not included. This is useful for dropping blanks, but it means a partial list silently shortens the document. To keep every page, your sequence must contain every page number once. Check the output page count against the input count in the result panel.
PDF has more than 50 pages on the free tier
Free limitFree tier caps PDFs at 50 pages and 2 MB. A long scanned bundle is blocked with: 'This PDF has N pages. Free handles up to 50 pages. Pro unlocks larger PDFs.' Pro raises the cap to 500 pages / 50 MB, Pro+Media to 2,000 pages / 500 MB. For a one-off long scan, split it with the range splitter, reorder each part, then recombine with the merge tool.
Scan file is larger than 2 MB
Free limitImage-heavy scans are big — a colour 300 DPI page can be 0.5–1 MB on its own. Free blocks files over 2 MB: 'Free handles files up to 2 MB per job. Pro unlocks larger files.' Shrinking the scan first with a compression tool, then reordering, keeps you under the cap; Pro raises the file limit to 50 MB.
You typed a range like 3-7
Silently truncatedThis tool does not accept range syntax. The order string is split on commas and each token is read as a single integer, so 3-7 is parsed as 3 and the -7 is discarded. Only page 3 gets added. List each page individually: 3, 4, 5, 6, 7. (Range syntax does work in the sibling delete-pages and extract-pages tools — but not here.)
A page number is out of range or zero
IgnoredNumbers below 1 or above the page count are filtered out before pages are copied — 0, -1, or 99 in a 10-page doc are skipped with no error. The risk is a quiet short output: if half your numbers were typos above the page count, you'll get fewer pages than expected. The output page count in the result panel is your check.
Same page number entered more than once
DuplicatedListing a page twice copies it twice. 1, 2, 2, 3 produces a 4-page PDF with page 2 appearing twice. This is intentional — it lets you repeat a cover or divider — but watch for accidental duplicates from a stray comma.
The scan is a single flattened image with no real pages
Not applicableSome 'scans' are one giant image, or a PDF where every visual page is actually a single PDF page. The reorder operates on PDF pages, not on the visual content inside a page. If your scanner produced a 1-page PDF, there is nothing to reorder — re-scan with one PDF page per sheet, or split the image first.
Box left empty
ErrorIf no valid page numbers are parsed from the box (empty, or only non-numeric text), processing fails with 'Enter at least one page number.' Type at least one page number to proceed.
Scan has an OCR text layer
PreservedIf the scan was already run through OCR (a searchable text layer behind the image), reordering copies each page intact, including its text layer — search still works in the reordered file. The tool does not add OCR; to make a non-searchable scan searchable, run the OCR tool first, then reorder.
Frequently asked questions
Is there a drag-and-drop thumbnail grid to rearrange pages?
No. The reorder tool has a single text box where you type the new page order as comma-separated numbers, e.g. 1, 3, 2, 4. There is no visual thumbnail grid, no drag-to-reorder, and no Reverse button. Open the scan in any PDF viewer to read off the current page numbers, then type the order you want.
Will reordering re-compress my scan or reduce its quality?
No. The tool copies each page object into a new document without re-rendering or re-encoding the image data, so scanned pixels are identical to the source — only the page order changes. File size stays essentially the same as the input.
How do I fix a duplex scan that came out as all fronts then all backs?
Interleave the page numbers. If a 6-page scan is file-page order 1,2,3,4,5,6 holding real pages 1,3,5,2,4,6, type 1, 4, 2, 5, 3, 6 to restore 1–6. Work out which file page holds each real page, then list them in real-page order.
What happens to a page I don't list?
It is dropped. The output contains only the pages you name. To keep the whole document, your list must include every page number exactly once. To intentionally remove a page (like a blank separator), just leave its number out.
Can I type a range like 1-10 instead of every number?
No — range syntax is not supported in the reorder tool. 1-10 is read as the single number 1. You must list each page: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. (Ranges do work in the delete-pages and extract-pages tools.)
Are pages numbered from 0 or from 1?
From 1. The first page is 1. Numbers below 1 or above the page count are ignored, so 0 does nothing.
How many pages can I reorder for free?
Free tier handles PDFs up to 50 pages and 2 MB. Larger scans are blocked with an upgrade prompt. Pro raises the cap to 500 pages / 50 MB, Pro+Media to 2,000 pages / 500 MB, and Developer to 10,000 pages / 2 GB.
Is my scanned document uploaded anywhere?
No. Everything runs in your browser using pdf-lib — the scan is read, reordered, and saved locally. The result panel confirms '0 bytes uploaded'. This matters for scans of IDs, medical records, or contracts.
Can I reorder a scan that's password-protected?
The tool loads PDFs ignoring encryption flags, so a permissions-restricted scan can usually be reordered. If the file has an open password you can't get past, remove it first with the remove-password tool.
My output has fewer pages than I expected — why?
Usually one of three things: you omitted page numbers (omitted pages are dropped), you typed numbers above the page count (those are ignored), or you used range syntax that got truncated. Compare the output page count to the input in the result panel and re-check your list.
Will OCR text or searchability survive the reorder?
Yes. Each page is copied whole, including any existing OCR text layer, so a searchable scan stays searchable after reordering. To add OCR to a non-searchable scan, run the OCR tool first.
Can I duplicate the cover page when reordering?
Yes — list its number more than once. 1, 1, 2, 3 puts page 1 at the start twice. Each occurrence of a page number adds a copy of that page.
Privacy first
All PDF processing runs locally in your browser using PDF-lib and pdf.js. No file is ever uploaded — only metadata counters are saved for signed-in dashboard stats.