How to make your digital signature to sign documents

Lots of people search for “make my digital signature” when what they really need is to sign a document without paper. We explain the two options: drawing your signature or using a digital certificate.

MultiDocs team2 min readUpdated on 29 October 2026With official sources

In 30 seconds

  • Draw your signature with your finger or mouse and use it straight away to sign a PDF.
  • Don't paste a scanned image of your signature into important documents: it's easy to copy.
  • If an official procedure in Spain asks for a “firma digital”, it means signing with a certificate or DNIe.

Option 1: draw your signature (the quickest)

  1. Open Sign for free on your phone or computer.
  2. Upload the document you want to sign (PDF or photo).
  3. Tap “Add signature” and draw your signature with your finger or mouse, slowly and large.
  4. Place it where it goes and download the signed document.

It's a valid electronic signature for most documents. Tip: don't keep an image of your signature to paste anywhere; sign on the document each time.

Official data

Art. 25

of the European eIDAS regulation: a signature cannot be denied validity just because it is electronic.

Source: EUR-Lex
96.3%

of people in Spain aged 16 to 74 used the internet in the last three months.

Source: INE, 2025

Option 2: digital signature with a certificate

If a public body asks you for a “digital signature” in the strict sense, you need a digital certificate or the DNIe (Spanish electronic ID card), and an application such as AutoFirma. It takes more work, but it's what some official procedures require.

How to tell which one you're being asked for

If the document is for the public administration and you're sent to an online government portal (sede electrónica), it will almost always be with a certificate or Cl@ve. If it's for a company, a school, a club or a person, signing it electronically and sending it back is usually enough.

Frequently asked questions

Can I make my digital signature for free?

Yes. You can draw your signature and sign documents for free on MultiDocs. The FNMT personal certificate is also free.

Is a signature made with a mouse legal?

Yes, it's an electronic signature under the European eIDAS regulation.

Official sources

We checked each source on 29 October 2026. If you spot outdated information, email us at info@multidocs.es.

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