Help
Frequently asked questions
Short answers about how easy it is, which apps we support, Genuine results, and what NotChanged does — and does not — prove.
- How easy is it to use?
- Very. Install the free browser extension or Android app, then download or share a PDF as you normally would. NotChanged stamps a verified copy in the background. To check a file later, open the verify page and upload it — no account needed for the person checking.
- What do I need to do as the person sending the document?
- Install once, then keep using the stamped file NotChanged saves (often named with -verified). Share or upload that file — not a copy re-saved in another PDF app.
- What do I need to do as the person checking the document?
- Open notchanged.com/verify, upload the PDF you were sent, and read the result. Genuine means the bytes still match the NotChanged record.
- Which extensions and apps are available?
- Chrome (and Brave), Microsoft Edge, Firefox, and Android. Each has its own download on the Get app page — Edge uses its own Download for Edge package with simple edge://extensions install steps.
- Is there a Safari or iPhone / iPad app?
- Not yet. There is no Safari extension and no iOS app at the moment. If you need NotChanged on Apple devices today, use Chrome, Edge, or Firefox on a computer, or verify PDFs on the website.
- What does Genuine mean — and what does it not mean?
- Genuine means the PDF bytes match a NotChanged record exactly. Depending on how the proof was made, that record also shows a download hostname (browser extension) or the Android app that shared the file (package and signing certificate). It does not mean a bank, employer, or other institution endorses the contents of the document.
- Why must I use the PDF saved by NotChanged?
- Only the PDF saved by the NotChanged extension or app will show as Genuine. Opening the file in another app and saving or exporting it again can change the bytes and remove authenticity, so verify will fail even if the document still looks the same. Always keep and send the stamped file from NotChanged.
- Do you store my PDF?
- No. We never store the file. We keep cryptographic hashes and metadata (such as hostname or sharing app identity) so anyone can verify later.
- Should I use the browser extension or the Android app?
- Use the browser extension when you download a PDF over HTTPS in Chrome, Edge, or Firefox. Use the Android app when you share a PDF from another app (for example a banking app) via Android’s share sheet. You can use both; they prove different paths.
- What is My Details, and is it required?
- Optional. You can add name, email, phone, and address in the extension or Android app. They may be shown on the verify page with new proofs and are not printed as raw personal data on the PDF stamp. Proofs work with none of these fields.
- Can someone fake a NotChanged stamp?
- A forged-looking badge without a matching registry record will not verify as Genuine. Trust the verify page (or API) result, not appearance alone. A real website or app can still hand over a forged PDF — Genuine attests origin/app identity and byte identity, not document truth.
- Is NotChanged on the Chrome Web Store, Edge Add-ons, or Google Play?
- Not yet. Today you install the Chrome, Edge, and Firefox packages from this site (Firefox as a temporary add-on until Mozilla signing) and the Android app as a free beta install from this site. We are working toward store listings.
- Who is this for?
- Individuals who want a stamped copy of what they downloaded or shared, and organisations that ask for bank statements, payslips, and similar PDFs — banks, brokers, estate agents, insurers, employers, universities, and more.
- How do I contact support?
- Email support@notchanged.com. See also our Privacy Policy and Terms of Service.
Still stuck? support@notchanged.com · Get the app · Verify a PDF