Hi Product Hunt! I’m the maker behind Chapa Lab. I built Firma Total because signing a PDF should not require uploading a sensitive document to someone else’s server. Firma Total lets you: ✍️ Draw, type or upload a visible signature 🔐 Create a verifiable PAdES signature with a .p12 or .pfx certificate 🇪🇸 Sign with AutoFirma and certificates such as FNMT or the Spanish electronic ID 🛡️ Protect existing signatures and detect expired certificates Everything is processed locally in your browser. Your PDF, certificate and password are never uploaded. There is no account, no subscription and no artificial usage limit. The source code is also public. I also wanted the product to be honest about an important distinction: placing an image of a signature on a PDF is not the same as cryptographically signing it with a digital certificate. Firma Total supports both, but explains clearly what each option provides. This is part of Chapa Lab, my collection of small, practical web tools designed to solve everyday problems without registrations or unnecessary data collection. I’d really appreciate your feedback, especially on the signing workflow, certificate compatibility and anything that could be explained more clearly. Thanks for trying it!

Firma Total

Sign PDFs locally with visible signatures or PAdES

Sign PDFs locally with visible signatures or PAdES