Everything you need to know about PDFHarbor — privacy, tools, file sizes, and more.
Your files are completely safe and we store absolutely nothing. For the vast majority of PDFHarbor tools, your PDF never leaves your device. It is read into your browser's memory using JavaScript, processed locally, and the result is downloaded directly to your device. We have no technical ability to access your file.
For a small number of advanced tools (PDF to Word), your file is sent over an encrypted HTTPS connection to our server, converted, returned to you, and immediately and permanently deleted. No backups, no logs, no copies.
No — for 34 out of 36 tools. Tools like The vast majority of PDFHarbor tools — 34 out of 36 — process your file entirely in your browser using pdf-lib and PDF.js.
The two exceptions are PDF to Word and certain advanced text processing — these require server-side conversion. Your file is encrypted in transit, processed, and deleted immediately. We are transparent about this on each tool's page.
No. For browser-based tools, your file never reaches our servers, so it is technically impossible for us to see its contents. The processing happens entirely inside your browser tab — it never goes over the internet.
For server-side tools, the file passes through our conversion server as an automated process. No human at PDFHarbor reviews, reads, or accesses your file contents.
Yes — for browser-based tools, it is as safe as it gets. Since your file never leaves your device, there is no risk of interception, breach, or unauthorised access. You could use PDFHarbor offline (after the page loads) and it would still work.
For server-side tools (PDF to Word), if you are working with highly confidential documents, we recommend using a browser-based alternative or your organisation's own licensed software. We do everything to protect your data, but transmitting sensitive files over the internet always carries some inherent risk.
We collect no personal data. We do not require an account, name, or email address.
We use Google Analytics to collect anonymous usage statistics — which pages are visited, how long people spend on the site, and what countries traffic comes from. This data is aggregated and anonymised; we cannot identify individual users from it.
We also display Google AdSense ads, which may use cookies to show relevant advertisements based on your browsing history. You can opt out of personalised ads via Google Ad Settings.
We use a small number of cookies from Google Analytics (_ga, _gid, _gat) and Google AdSense. We do not use any proprietary tracking cookies of our own.
Cookies are not required for any tool to function. You can disable cookies in your browser settings without affecting your ability to use PDFHarbor tools.
Most PDFHarbor tools use two open-source JavaScript libraries that run directly in your browser:
When you upload a file, your browser reads it into memory. The library processes it according to the tool's function, and the result is generated as a download — all without touching the internet.
No. PDFHarbor runs entirely in your web browser. No software installation, no plugins, no extensions required. Any modern browser (Chrome, Firefox, Safari, Edge) on any device works.
Partially. Once the page has loaded in your browser, the browser-based tools will continue to work even if your internet connection drops — because all processing happens locally. However, the page itself needs an internet connection to load initially (to fetch the JavaScript libraries and styles).
Server-side tools (PDF to Word) require an active internet connection at all times.
PDFHarbor is free because our browser-based tools are built on open-source libraries that cost nothing to run. Our hosting costs are modest (Azure Static Web Apps free tier + a small conversion server).
We sustain the site through Google AdSense advertising. We are actively building 8 professional tools powered by Adobe's PDF API which may have a small per-use fee, but all 36 browser-based tools will always remain free.
No. PDFHarbor requires no account, no sign-up, and no email address. Every tool is available immediately with no registration. We believe PDF tools should be as frictionless as possible.
PDFHarbor primarily works with PDF files (.pdf). Some tools also accept:
We do not currently support Word-to-PDF, Excel-to-PDF, or other office format conversions (these are planned for future Adobe API-powered tools).
There is no hard file size limit set by PDFHarbor. However, practical limits apply:
If you're processing a very large PDF, try splitting it first using our Split PDF tool, then processing the sections separately.
Yes, with some nuances:
For most tools (merge, split, rotate, protect, watermark, page numbers), the output is visually identical to the input — we modify the PDF structure, not the visual content.
For tools that involve rendering (Grayscale PDF, PDF to Images), each page is rasterised at 2× resolution and re-encoded as an image. This means:
For the best quality on conversion tools, start with a high-quality source PDF.
This happens when your PDF is a scanned document — the pages are images of text rather than actual text. PDF.js can only extract text that is embedded as real text in the PDF structure.
Solutions:
Some tools support multiple files and some don't:
Batch processing (applying the same operation to many files at once) is a planned feature for a future Pro tier.
PDF to Word conversion is one of the hardest problems in document processing. PDFs are designed for display, not editing — they don't store text in the logical order you read it, and they embed fonts and layouts in complex ways.
Our current PDF to Word tool uses Stirling PDF (an open-source converter) which handles most straightforward documents well but may struggle with:
We are building an Adobe API-powered version which will deliver significantly better results, especially for complex documents. This will be available as a premium tool soon.
Our E-Signature tool lets you draw, type, or upload a signature image and place it anywhere on a PDF page. The signature is embedded as an image directly into the PDF using pdf-lib.
On legal enforceability: a simple image-based signature embedded in a PDF is generally enforceable in many jurisdictions for low-stakes documents, but it does not provide cryptographic signing, audit trails, or identity verification. For legally binding contracts, medical documents, financial agreements, or regulated industries, we strongly recommend using a dedicated e-signature service such as DocuSign, Adobe Sign, or HelloSign, which provide certified digital signatures with full audit trails.
No — once you download the processed file, changes cannot be undone by PDFHarbor. We recommend always keeping a copy of your original PDF before making changes.
One exception: some operations are reversible by using another tool (e.g. you can split a merged PDF, or remove a watermark using the Redact tool).
Browser-based PDF compression has limitations. Our tool re-encodes the PDF structure to remove redundancy, but cannot deeply re-compress embedded images (which are often the largest part of a PDF) without degrading quality.
You'll see the best results on PDFs that have uncompressed content, redundant objects, or metadata bloat. For PDFs that are mostly high-resolution images (e.g. scanned documents), the savings will be modest.
For maximum compression, consider Adobe Acrobat's "Reduce File Size" feature or our upcoming Smart Compress tool (Adobe API-powered) which applies AI-driven image compression.
These tools use the standard PDF fonts built into pdf-lib, which are available on all PDF viewers without embedding:
Custom fonts (e.g. your brand font) are not currently supported in these tools. Our PDF Text Box Editor supports a wider range of fonts.
Yes, completely free — all 36 current tools cost $0 to use, with no hidden charges, no watermarks on output files, no usage limits, and no credit card required.
We sustain the site through advertising (Google AdSense). In the future, some premium tools powered by Adobe's API may have a small per-use fee to cover API costs — but these will be clearly marked and the core tools will always remain free.
Possibly in the future — but our core tools will always be free. We are considering:
We have no current timeline for this. Our priority is building the best free tool suite possible first.
No, never. PDFHarbor does not add watermarks, branding, or any modifications to your output files beyond what you explicitly requested. The files you download are clean and unmodified except for your chosen operation.
Try these steps in order:
PDF to Word conversion is complex and our current tool (powered by Stirling PDF) may not handle all documents perfectly. Common issues and fixes:
We are building an Adobe API-powered version that will handle these cases much better.
This usually means the output file is corrupted. Try:
If the problem persists, contact us at support@pdfharbor.net with details and we'll help troubleshoot.
Yes — PDFHarbor is mobile-responsive and works on iOS and Android browsers. However, some tools may perform better on desktop because:
For best results with large or complex PDFs, we recommend using a desktop or laptop.