Security & Sign

Sign PDF Online

Add a visual signature to PDF documents. Draw, type or upload a signature image, then position it on the pages you choose.

Select PDF Document to Sign

Drag & drop your PDF here or choose from your computer

100% Client-Side Privacy: Signatures are embedded directly on your device

This tool places a visual signature mark; it does not verify identity or create a certificate-backed digital signature. Editing an already digitally signed PDF can invalidate its existing signature.

QUICK & EASY TUTORIAL

How to Sign PDF Online in 3 Simple Steps

Add a visual signature to a PDF in three steps. This tool places a signature image or mark on the page; it does not provide identity verification or a certificate-backed digital signature.

01
STEP 01

Upload Your File

Choose a PDF from your device or use the sample agreement to try the signing workspace.

Browser-side PDF editing
02
STEP 02

Customize & Configure

Draw a signature, type your name in a script font, or upload a PNG, JPEG or WebP image. Drag and resize it on the page.

Precise controls • Live preview
03
STEP 03

Process & Download

Review your placements, save a new PDF copy and check the exported document before sharing.

Review before download
TRUST & RELIABILITY

Why Users Prefer Our Sign PDF Online

Create a visible signature mark and place it on selected PDF pages. Review the controls and practical limitations before using the exported document.

SIGNATURE DRAWING

Draw a Signature

Use a mouse, trackpad, stylus or touch screen to draw a signature in the signature pad.

SCRIPT FONTS

Type a Signature

Type a name and choose one of the available cursive font styles to create a visual signature mark.

IMAGE UPLOAD

Upload a Signature Image

Add a PNG, JPEG or WebP image of a handwritten signature. Transparent PNG files are usually best for clean placement.

PAGE PLACEMENT

Position and Resize

Move, resize, duplicate or remove signature marks on the page preview. You can copy an element to other pages.

PRACTICAL STAMPS

Add Page Stamps

Add a date, initials, checkmark or an APPROVED graphic stamp to a PDF page.

RESPONSIVE WORKSPACE

Download a New PDF

Export a modified PDF copy with the selected visual marks embedded into page content.

VISUAL WORKFLOW & DEMO

See How It Works: Before & After sign pdf

Experience lightning-fast document processing with zero server uploads and studio-grade visual output.

Before: Unmarked Draft Document
Vendor_Service_Agreement.pdf
Example PDF · Visual signature mark
Example document Visual signature preview
Stamped in 0.2s 100% In-Memory
After: Official Executed Document
Vendor_Agreement_Executed.pdf
Example PDF · Visual signature mark
Vector Stamps • Crisp Lettering at 1200 DPI
Signature mark placed Positioning controls Preview before export
SPECIFICATIONS & PLATFORMS

Supported Formats & Device Compatibility

The page uses PDF.js 3.11.174 for page previews and PDF-Lib 1.17.1 for PDF export. Browser memory, PDF structure and device capabilities affect compatibility.

📄

PDF Input

  • ✓ PDF files that the included PDF.js version can open
  • ✓ Encrypted PDFs must be unlocked before upload
  • ✓ Scanned pages can receive visual signature marks
  • ✓ Damaged or unusual PDFs may fail to load or export
⚡

Frontend Limits

  • ✓ Maximum PDF file size: 100 MB
  • ✓ Maximum PDF length: 500 pages
  • ✓ One PDF is processed per session
  • ✓ Signature images: PNG, JPEG or WebP up to 5 MB
💻

Devices

  • ✓ Modern browser with JavaScript enabled
  • ✓ Desktop and mobile layouts are supported
  • ✓ Large documents need sufficient available memory
  • ✓ Keep the browser tab open until export completes
🌐

PDF Libraries

  • ✓ PDF.js 3.11.174 renders page previews
  • ✓ PDF-Lib 1.17.1 writes the updated PDF
  • ✓ Libraries are loaded from external CDNs
  • ✓ Complex forms and annotations need review after export
PRIVACY BY DESIGN

How This PDF Signing Tool Processes Your File

The supplied sign-pdf.js reads the selected PDF in browser memory and uses PDF.js and PDF-Lib to preview and export it. These libraries and the signature fonts are loaded from external services.

🛡️

PDF Processing in the Browser

The supplied tool script reads the selected PDF with the browser File API and passes its bytes to PDF.js and PDF-Lib. The script does not send the selected PDF to an application upload endpoint.

🧹

Temporary Page Memory

The PDF bytes, signature image data and page previews remain in the active browser session while the tool runs. Use Start Over or close the tab when you finish.

⚖️

External Library and Font Requests

PDF.js, PDF-Lib and signature fonts are loaded from external CDNs or font services. This source review does not audit shared scripts, analytics, browser extensions or every request made by the deployed website.

Zero Server Uploads
Client-Side Processing
No Document Data Stored
No Account or Sign-Up Required
TECHNICAL ARCHITECTURE

Engineered for Privacy & Efficiency

A summary of the visible signing workflow and its PDF libraries. Compatibility and export results depend on the source PDF and browser.

3 Methods
Signature Creation
Draw, type or upload a signature image.
PDF.js
Page Preview
Renders the selected PDF pages in the browser.
PDF-Lib
PDF Export
Embeds placed visual marks in a new PDF copy.
New Copy
Original File
The tool exports a modified copy and does not overwrite your selected source file.
PDF.js Preview
PDF-Lib Export
Visual Signature Marks
Browser-Based Workflow
COMPLETE GUIDE & SPECIFICATIONS

The Complete Guide to Signing PDF Documents Electronically

Learn what this tool adds to a PDF, how the export works, and which document features need extra care.

1

What Does This PDF Signing Tool Add?

It adds a visual mark to the page, rather than a certificate-backed digital signature.

The tool creates a signature image by drawing, typing a name in a cursive font, or uploading a signature image. PDF-Lib embeds that image into the page content.

  • Visual signature: The result looks like a signature on the page, but it does not prove the signer's identity.
  • No certificate signing: The tool does not create a cryptographic signature field, certificate chain or trusted timestamp.
  • Review the result: Open the exported PDF in another viewer and confirm that every mark is in the right place.
2

How to Place a Signature on a PDF

Create the mark first, then position it on the page preview.

Use the page controls to navigate the document. Drag a placed mark to move it, use its resize handle to change its size, or use the item actions to duplicate or delete it.

  • Draw: Sign with a mouse, trackpad, stylus or touch screen.
  • Type: Enter your name and choose an available script style.
  • Upload: Use a PNG, JPEG or WebP signature image. A transparent PNG usually blends best.
3

Electronic Signature and Legal Validity

Legal effect depends on the applicable law, transaction and signing process.

This page creates a visual electronic signature mark only. It does not verify identity, capture recipient consent, create a tamper-evident certificate signature or provide a trusted audit trail.

  • Jurisdiction matters: Requirements differ by country, document type and transaction.
  • Formal workflows: Some transactions require identity checks, consent records, witness or notary steps, or a qualified trust service.
  • Get appropriate advice: For important legal documents, confirm the signing requirements with a qualified professional.
4

PDF Forms, Annotations and Existing Signatures

Rewriting a PDF can affect interactive document features.

The optional form-field setting can flatten AcroForm fields when supported by PDF-Lib. It does not flatten every annotation, layer or interactive feature.

  • Form fields: Flattening makes supported AcroForm fields part of the page appearance; keep an editable original if needed.
  • Annotations: Review comments, links, attachments and other annotations after export.
  • Existing digital signatures: Modifying a signed PDF generally invalidates its existing cryptographic signature. Do not use this workflow when signature preservation is required.
5

Practical File Limits and Best Practices

Large and complex PDFs may need more browser memory.

The updated frontend will validate file size and page count before opening a document. The configured limits are frontend safeguards, not a guarantee that every device can process files at the limit.

  • Keep the original: Save an untouched copy before modifying an important document.
  • Password protection: Unlock encrypted PDFs before upload; this page does not provide a password-entry interface.
  • Check the export: Inspect the output, especially mixed-size pages, forms, annotations and scanned documents.
REAL-WORLD APPLICATIONS

Tailored Solutions for Every sign pdf Workflow

Use the visual signing workspace for common document review and approval workflows. This tool places marks; it does not provide identity verification or notarization.

⚖️
Legal & Contracts

Agreements and Contracts

Place a visible signature mark on a contract or agreement before sharing the updated PDF.

✓ Visual PDF mark · Review the exported copy
📊
Corporate & Finance

Business Forms

Add a typed or handwritten signature image to forms that accept visual electronic signatures.

✓ Visual PDF mark · Review the exported copy
🎓
Academic & Research

Invoices and Purchase Orders

Add a signature, initials or date mark to a PDF invoice or purchase order.

✓ Visual PDF mark · Review the exported copy
💼
HR & Operations

School and University Documents

Sign permission forms, applications and other documents that accept a visual signature.

✓ Visual PDF mark · Review the exported copy
🧾
Tax & Bookkeeping

Internal Approvals

Place an APPROVED graphic, initials or checkmark on an internal review document.

✓ Visual PDF mark · Review the exported copy
🩺
Healthcare & Records

Scanned Documents

Add a signature image to scanned PDFs when a visible mark is all that is required.

✓ Visual PDF mark · Review the exported copy
DIAGNOSTICS & QUICK FIXES

Common Issues & Troubleshooting Fixes

Practical checks for signature images, page placement, PDF loading and export issues.

🔒

Signature Image Has a White Background

Possible cause: The source image may contain an opaque background rather than transparency.

✓ Instant Solution

Use a transparent PNG where possible. JPEG files normally have a solid background; the tool converts supported images to PNG for embedding but cannot remove the original background.

📦

The Signature Looks Too Large or Small

Possible cause: The initial placement size may not match the page or the signature artwork.

✓ Instant Solution

Select the placed mark and use its resize handle. Review the exported PDF at normal zoom before sharing.

⚠️

A PDF Will Not Open

Possible cause: The file may be damaged, encrypted, too large or unsupported by the PDF parser.

✓ Instant Solution

Confirm the PDF opens in another reader. Unlock password-protected files first and stay within the tool's configured file and page limits.

📐

A Mark Appears in the Wrong Position

Possible cause: Page rotation, unusual page boxes or a mismatch between preview and export coordinates may affect placement.

✓ Instant Solution

Use the updated page preview, check the source page orientation and inspect the exported copy. Keep the original document.

📝

Form Fields Are No Longer Editable

Possible cause: The optional form-field flattening option can convert supported AcroForm fields into page content.

✓ Instant Solution

Turn off the form-field flattening option if you need to keep supported fields editable. This option does not flatten all PDF annotations or layers.

🔁

The Browser Slows Down During Export

Possible cause: Large PDFs and high-resolution signature images can use substantial memory.

✓ Instant Solution

Try a smaller PDF, reduce the size of the uploaded signature image, close unused tabs and process one document at a time.

POWER TIP

Important: A visual signature image is not a cryptographic digital signature. Keep the original PDF and verify legal and signing requirements before using the output.

QUESTIONS & ANSWERS

Frequently Asked Questions

Questions regarding drawn signatures, typed signatures, PNG stamps, legal validity, and security.

Q What methods can I use to sign my PDF document?

You can sign by drawing your signature with a mouse or touchscreen, typing your name with elegant cursive calligraphy fonts, or uploading a transparent PNG image of your actual handwritten signature.

Q Are electronic signatures created here legally binding?

Yes. Electronic signatures created with OnlineConvertPDF comply with the US ESIGN Act, the Uniform Electronic Transactions Act (UETA), and EU eIDAS regulations for standard electronic signatures.

Q Can I add date stamps, signer names, and custom initials?

Yes! Alongside your signature, you can place current date stamps, printed full names, corporate job titles, and initial boxes anywhere on the document.

Q Can recipients remove or copy my signature from the downloaded PDF?

You can choose to 'Flatten Document Upon Download'. When flattened, your signature is permanently fused into the page vectors, making it impossible to select, copy, or move.

Q Are my signatures or confidential contracts saved on your servers?

No, never. The canvas drawing and PDF stamping happen entirely inside your local web browser session. No signatures or documents are ever stored or uploaded.

USER COMMUNITY & SUPPORT

Help Us Improve sign pdf

Encountered an issue with a document, or have an idea to make this tool better? Share your thoughts directly with our engineering team.