March 20, 2026DottSign Team

What Is a Digital Signature and Why Does It Matter?

A plain-English explanation of digital signatures, how they work legally, and why they're more secure than a scanned image of your handwriting.

Digital vs. Electronic Signatures

Many people use "digital signature" and "electronic signature" interchangeably, but they mean different things:

  • Electronic signature — any electronic indication of intent to agree, including a typed name, a checkbox, or a drawing.
  • Digital signature — a specific type of electronic signature backed by public-key cryptography and a digital certificate.

DottSign uses digital signatures, which offer a much higher level of security and legal standing.

How It Works

When you sign a document with DottSign, we:

  1. Generate a unique cryptographic hash of the document content.
  2. Encrypt the hash using a private key tied to your identity.
  3. Embed the resulting signature block inside the PDF alongside a public certificate.

Anyone with the public certificate can verify that:

  • The signature belongs to you.
  • The document has not been modified since it was signed.

Verify Any DottSign Document

You don't need an account to verify a document. DottSign provides a public verification page where anyone can upload a signed PDF and instantly confirm:

  • Whether the signatures are authentic and belong to the claimed identities.
  • Whether the document has been tampered with after signing.
  • Who signed and when.

Visit dottsign.com/verify and upload the PDF — results appear in seconds, no login required.

Why It's More Secure Than a Scanned Signature

A scanned image of your handwritten signature can be copy-pasted into any document. There's no link between the image and the document content — it's just pixels.

A digital signature, on the other hand, is mathematically linked to the exact bytes of the document. Change even a single character and the verification fails.

Legal Standing in Brazil

Digital signatures using ICP-Brasil certificates have the same legal weight as a notarized handwritten signature under Brazilian law (MP 2.200-2/2001). DottSign uses this standard to ensure your contracts are fully enforceable.

When to Use DottSign

DottSign is ideal for:

  • Service agreements — freelance contracts, consulting agreements.
  • HR documents — employment offers, NDAs, onboarding forms.
  • Real estate — lease agreements, purchase proposals.
  • Legal documents — any contract where proof of signature integrity matters.

Ready to sign your first document? Create a free account and get started in minutes.

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What Is a Digital Signature and Why Does It Matter? · DottSign