ORIGINAL CROSS-FILE PAGE-ORDER STUDY · 18 SEPTEMBER 2026
Does a reordered PDF keep the exact cross-file page sequence?
In PaperGrid's deterministic six-page browser test, all eight checks passed. The output reopened in the planned interleaved order C2, A1, B2, C1, A2, B1, with every marker still selectable and every page renderable.
The test copied one requested page at a time from three two-page synthetic PDFs, following the same page plan used by PaperGrid's unified organizer. It supports this measured run only and is not a guarantee for every PDF.
C2, A1, B2, C1, A2, B1
Every marker remained selectable
Order, geometry and rendering
| Check | Result | How it was verified |
|---|---|---|
| Output reopened | Pass | Loaded again with pdf-lib and PDF.js |
| Page count | 6 of 6 | Both readers reported six pages |
| Cross-file page order | 6 of 6 exact | Extracted labels matched C2, A1, B2, C1, A2, B1 |
| Selectable marker text | 6 of 6 | PDF.js extracted the expected label from every page |
| Page rotations | All preserved | Expected 180° and 90° pages remained rotated |
| Page dimensions | 6 of 6 | All portrait, landscape and custom dimensions matched |
| Custom crop box | Preserved | x 12, y 18, width 396, height 559 |
| Output rendering | 6 of 6 | PDF.js rendered every output page |
METHOD
How the page-order test was run
- Three deterministic two-page PDFs were generated with unique selectable labels, different page dimensions, 90° and 180° rotations, and one custom crop box.
- The planned output alternated source documents deliberately: C2, A1, B2, C1, A2, B1.
- Each source was loaded once. The requested page was copied and added to the output in unified-grid order, matching the production custom-order merge sequence.
- The output was reopened with pdf-lib for geometry checks. PDF.js independently extracted each marker and rendered all six pages.
- Source and output SHA-256 hashes, exact bytes, time, geometry and pass/fail decisions were recorded in the downloadable JSON.
What this supports
- All six requested cross-file positions survived this run.
- Every tested marker remained selectable.
- The tested rotations, sizes and crop box survived.
- The saved output reopened and rendered fully.
What it does not prove
- That every advanced PDF feature survives.
- That forms or signatures remain functional.
- That every font renders pixel-identically.
- That encrypted or damaged PDFs can be organized.
Product-control boundary
This harness measures the production page-copy sequence directly. Separate automated product tests cover the visible organizer, accessible movement controls, exact output order, mobile width, CSP and returning-user offline operation.
REPRODUCE AND INSPECT
Run or download the exact evidence
The public lab rebuilds the safe sources, applies the same page plan and displays its own browser measurements. The machine-readable dataset records the cited run's exact hashes and results.
QUESTIONS & ANSWERS
Cross-file page-order FAQ
Can PaperGrid interleave pages from different PDFs?
Yes. The visual organizer lets users arrange selected pages across source-file boundaries. In this deterministic test, the output reopened in the exact planned order C2, A1, B2, C1, A2, B1.
Did reordered PDF text remain selectable?
Yes for the six synthetic marker labels in this run. The study did not cover every font, language or complex text encoding.
Does this prove every PDF can be reordered safely?
No. This is one deterministic synthetic study. Encrypted or malformed PDFs, forms, signatures, portfolios and embedded files were not tested.
Can the page-order test be reproduced?
Yes. The public browser lab generates the fixtures, runs the same custom-order page-copy sequence, reopens the output, extracts text and renders every page locally.