Add Your Signature to Any PDF — Free & Private
Type, draw, or upload your signature and place it anywhere on your PDF. Download instantly — no account required.
Draw your signature above using mouse or touch
Click to upload a PNG or JPG signature
PNG with transparent background works best
What this tool does
This free PDF signature tool lets you add a signature to any PDF online without uploading your file to a server. All processing runs entirely inside your web browser using PDF.js (for rendering) and PDF-lib (for embedding your signature into the PDF).
You can sign PDF forms, contracts, agreements, and documents in seconds. Choose from three signing methods: type your name in a stylish handwriting font, draw it freehand using your mouse or touchscreen, or upload a photo of your existing signature. Once placed, drag and resize the signature to fit perfectly — then download the finished PDF instantly.
Unlike cloud-based tools that transmit your files to remote servers, our browser PDF signature tool keeps your documents completely private. Your PDFs are never sent anywhere — they stay on your device from start to finish. Need to reduce your PDF's file size after signing? Try our Compress PDF tool.
Key features
Type your name in one of 5 stylish handwriting fonts with color options. Draw freehand with pen size and color controls. Or upload a PNG/JPG image of your existing signature.
Place your signature exactly where it needs to go. Drag to move, use corner handles to resize, and use the rotation handle to adjust the angle precisely.
Navigate between pages and sign each one individually. All signatures are embedded together when you download the final signed PDF.
No server upload, no account, no watermark. All signing logic runs locally using open-source JavaScript libraries — PDF.js and pdf-lib.
Click "Download Signed PDF" and your signed file is ready immediately, saved directly to your device.
Zero network transmission of your files. Sensitive contracts, legal documents, and personal PDFs remain entirely under your control throughout the process.
Supported files & limits
Input Format: PDF files (.pdf). Supports standard single and multi-page PDF documents.
Signature Formats:
- Typed: rendered to canvas using Google Fonts handwriting styles
- Drawn: freehand canvas drawing with customizable pen color and size
- Uploaded: PNG, JPG, GIF, or WebP image — PNG with transparency recommended for cleanest results
Output Format: Signed PDF with your signature embedded as an image at the position and size you set. Original PDF content, formatting, and metadata are preserved.
File Size: No server-side limits. Practical limits depend on your device's available memory. Files under 100MB work best, with very large or complex PDFs potentially taking a moment to render.
Security & privacy
This tool is built on a client-side-only architecture that prioritizes your document security. When you sign a PDF:
1. No file upload occurs. Your PDF is read by the browser's FileReader API and never leaves your device. The file is processed entirely in memory using JavaScript.
2. No server infrastructure is involved. PDF rendering (PDF.js) and PDF writing (pdf-lib) both run as JavaScript in your browser tab. There is no backend, no database, and no intermediate storage of any kind.
3. No data retention. When you close the browser tab, all loaded data is cleared from memory. Nothing persists between sessions.
4. Transparent code execution. As a client-side web application, all operations are visible through your browser's developer tools. There are no hidden network requests or undisclosed processing steps.
This makes it ideal for signing sensitive documents — legal contracts, financial forms, medical paperwork, and confidential agreements — where you cannot risk your files being accessed or stored by third parties.
Frequently asked questions
You can add a signature to a PDF online for free using CleanPDF. Simply upload your file, create your signature by typing, drawing, or uploading an image, place it on the document, and download instantly without login.
This tool allows you to sign a PDF without uploading it. All processing happens locally in your browser, ensuring your file never leaves your device.
Yes, it is completely safe. Your PDF is never uploaded or stored. Everything is processed locally in your browser for maximum privacy.
Yes, you can sign PDFs on mobile devices. You can draw your signature using your finger or stylus directly on your screen.
Yes, you can navigate through pages and add your signature wherever needed. All signatures will be included in the final downloaded PDF.
CleanPDF is one of the best free PDF signature tools that requires no login. It is fast, secure, and works entirely in your browser.
Electronic signatures are legally valid in many countries under laws like ESIGN and eIDAS. For highly sensitive documents, certified digital signatures may be required.
There is no strict limit, but files under 100MB provide the best performance depending on your device.
Yes, you can draw your signature using your mouse or touchscreen with customizable pen options.
Yes, you can upload a PNG, JPG, or WebP image. Transparent PNG works best for clean signatures.
No, your signed PDF will not contain any watermark and is ready for professional use.
No, this is a browser-based tool that works instantly without installation.
Yes, it works on all operating systems with a modern browser.
Yes, you can drag, resize, and rotate your signature to place it exactly where needed.
This tool is part of our PDF Tools collection.