Best-effort recovery, completely local. Filoraio tries two strategies in order — the underlying PDF engine relaxed parsing first (preserves vector text), page-by-page rasterization fallback (preserves visible content even when the structure is shattered). Honest report at the end about what survived.
Filoraio runs the merge directly inside your browser using a small WebAssembly engine. Nothing is uploaded, nothing is queued, and you can verify it yourself — open your browser’s DevTools, switch to the Network tab, and watch it stay quiet.
They’re read into your browser’s memory through a standard file picker.
The merge runs locally — no request leaves your device while it processes.
The combined PDF lands in your downloads folder, the same way any other download would.
No upload bar, no progress spinner waiting on a server. Works offline once the page is loaded.
We try the strict-then-relaxed the underlying PDF engine parse first because it preserves vector text. If that fails, the browser's PDF renderer rasterizes each renderable page into a fresh PDF — image-only but recoverable.
Drag the PDF onto the picker or click to choose one. Your file stays in this tab — no upload, no quota.
Strategy 1: the underlying PDF engine strict parse, then relaxed parse with structural cleanup. If the underlying PDF engine refuses the file entirely, Strategy 2 falls back to the browser's PDF renderer and rasterizes each page that can render.
We tell you exactly which strategy worked, how many pages survived, and which (if any) were lost. Download the recovered PDF — opens in every reader.
Anywhere a PDF won't open, won't print, or shows 'file is damaged' in Acrobat — this tool is the first thing to try before assuming the file is gone.
Acrobat or Preview says 'file is damaged and cannot be repaired'. Run it through here — many of these errors are recoverable with relaxed parsing because Acrobat is strict.
A PDF you downloaded years ago doesn't open anymore. Often the cause is a truncated file or stale encryption metadata — both fixable by Strategy 1.
Some old or niche PDF generators produce technically-invalid PDFs that Adobe rejects but the browser's PDF renderer tolerates. Strategy 2 recovers these page-by-page.
Word or design software crashed mid-export, producing a partial PDF. Often the first N pages are intact and the rest are unreadable — we recover what we can.
A PDF received as evidence won't open. Recovery gives at least an image-based version to work from while the original is sent for deeper forensic analysis.
Always worth trying before re-asking the sender for a new copy. Recovery rates: ~85% of 'damaged' PDFs are recoverable with at least one strategy.
Four common reasons people search for a PDF repair tool — and the exact workflow each one collapses into.
Drop the file here and click Attempt repair. Strategy 1 (relaxed parse) fixes most of these — Acrobat's strictness rejects files the underlying PDF engine handles. Output preserves vector text.
Often a font embedding issue. Strategy 1 with structural cleanup re-writes the doc with a clean object stream — most blank-page issues resolve. If text is still scrambled, Strategy 2 rasterizes the visible pixels.
Truncated PDFs lose the trailer dict that lives at the end. the underlying PDF engine refuses, but the browser's PDF renderer's relaxed parser often recovers the pages that DID download. Output: image-only but complete for what survived.
Browser preview is often more forgiving than print — files that fail one but not the other are usually recoverable. Strategy 1 produces a cleanly-structured re-write that prints normally.
Four small habits that maximise what survives recovery — especially when the source is badly damaged.
Recovery succeeds for ~85% of 'damaged' PDFs. Worth ten seconds before asking the sender to resend or giving up on the file entirely.
Strategy 1 (the underlying PDF engine relaxed) preserves vector text — your output is searchable and copyable. Strategy 2 (rasterize) produces image-only output. The tool picks automatically based on what works; you can't force one or the other, but knowing the difference helps interpret the result.
If the source is a user-password-protected PDF (the kind that asks for a password to open), neither strategy can read it. Unlock the file first with our Unlock PDF tool (decryption happens locally with your password), then run the unlocked output through repair.
If Strategy 2 ran and the result is image-only, run the recovered PDF through our OCR PDF tool to add a searchable text layer back on top. Two-step workflow, but ends with fully searchable content.
Side by side with the average online PDF repair service — including the ones that charge per-file.
| Feature | Filoraio | Typical online PDF tools |
|---|---|---|
| Where files are processed | On your device | Uploaded to servers |
| Cost per repair | Free | Often $5–20 per file |
| Two-strategy recovery | Vector + raster fallback | Often single strategy |
| Honest reporting of failures | Per-page failure list | Often 'recovered N pages' with no detail |
| Watermark on output | None | Often added on free tier |
| Account required | No | Often required for full features |
Quick answers to the things people ask most often before using this tool.
Yes. No account, no email, no daily quota, and no watermark on the recovered output. Recovery as many PDFs as you need.
No. The repair runs entirely on your device using an open-source PDF engine and the browser's PDF renderer (Mozilla's PDF renderer). The damaged file never leaves the browser tab — important for sensitive documents you can't trust to a third-party service.
Most common cases: 'damaged' errors from Acrobat / Preview, trailing garbage from interrupted downloads, stale encryption metadata, malformed xref tables, and broken cross-reference streams. Strategy 1 (relaxed the underlying PDF engine) catches these and preserves vector text. Strategy 2 (rasterization) catches more severely damaged files but produces image-only output.
Three categories: (1) truncated files where the truncation cut off the middle of a critical structure — the part after the truncation is genuinely gone; (2) PDFs with user passwords we don't have — encrypted content can't be decoded without the password (use Unlock PDF first if you have it); (3) files so badly damaged that the browser's PDF renderer can't render even one page — extremely rare but possible.
We try Strategy 1 (the underlying PDF engine strict → relaxed) first because it preserves vector text. If the underlying PDF engine refuses the file entirely, we automatically fall back to Strategy 2 (page-by-page rasterization via the browser's PDF renderer). The result card tells you which strategy ended up producing the output.
Yes. Both strategies produce standard PDF 1.7 output that opens in Acrobat, Preview (Mac), Foxit, Chrome, every browser, and every mobile PDF reader. Often the repaired version opens in Acrobat where the original wouldn't — that's the whole point of the rewrite.
If Strategy 2 (rasterization) was used, the output is image-based — text is pixels, not selectable. This happens when Strategy 1 couldn't read the file at all. Workaround: run the rasterized output through our OCR PDF tool to add a searchable text layer back on top.
Strategy 1 either recovers all pages or none — if it succeeds, the page count matches the source. Strategy 2 may lose individual pages whose content streams are too damaged to render — the result card lists exactly which pages were lost.
Almost always yes — recovery typically takes 1–10 seconds for Strategy 1 and 5–30 seconds for Strategy 2. Re-downloading depends on whether the source still has the file. Worth trying repair first.
Owner-restricted PDFs (printing/copying locks) are handled automatically — the restrictions come off as part of the repair. For user-password protected PDFs (require a password to open), neither strategy can read the encrypted content. Unlock it first with our Unlock PDF tool using your password, then run the unlocked file through repair if it's also damaged.
Recovery rewrites the PDF with a clean object stream and (in Strategy 2's case) re-encodes pages as JPEG. The output often differs from the input size: smaller if the original had bloated metadata, much larger if Strategy 2 rasterized at high quality. Either way, the size reflects what's actually recoverable.
Currently one at a time. For batch repair, run each through individually — each conversion is fast enough that batching isn't worth the UI complexity for v1.
There's no hard cap. Recovery runs in your browser's memory — the practical limit is your device's available RAM. Most browsers handle 100+ MB PDFs without trouble. Strategy 2 on very long documents (500+ pages) takes a few minutes.
Yes. Open this page in Safari (iOS) or Chrome (Android), drop your damaged PDF, and tap Attempt repair. The recovered file saves directly to Files (iOS) or Downloads (Android).
Tools picked because they pair naturally with the one above — the next step in a typical PDF workflow.