Quick Sign (Mobile-friendly)
Sign a PDF using a phone photo of your handwritten signature on a piece of white paper — no need to manually create a transparent PNG first.
1. Upload your files (min 2)
How does the Quick Sign (Mobile-friendly) work?
Sign a PDF straight from a phone photo of your signature — no need to upload a transparent PNG. Take a photo of your signature on a clean white piece of paper, drop it in along with the PDF, and the tool removes the white background using a luma threshold so the signature pastes cleanly onto the page. Pick a placement (bottom-right is the convention), set a width, and download. Differs from the regular Sign PDF tool, which expects you to provide an already-transparent PNG. If your signature comes out patchy, try the Conservative threshold; if you see ghosty white edges, try Aggressive.
🔒 Security & Privacy
All processing happens on your device. Your files never leave your browser, never touch our servers, and are not stored anywhere. Close the tab and the file is gone.
📱 Use it on any device
Works in any modern browser — Mac, Windows, Linux, iPhone, Android, and tablets. No installation, no app to download. Just open the page and start.
⚡ Quick & easy
Drag, drop, click. Most files process in seconds, not minutes. No watermarks added to your output, no per-day limits, and the tool always shows the result before asking you to download.
🎁 Always free, no signup
Free to use, every time. No account creation, no email required, no “trial” that converts to a paid plan. We make money from ads so you don’t have to pay.
Frequently asked
For heavier PDF workflows
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