A web alternative to FirmaEC for signing PDFs
Does FirmaEC need Java, or does its mobile app cap your document at 4 MB? firmar.ec signs PDFs up to 50 MB with your .p12 certificate in the browser, with no install. Free and open source.
By IDK Manager Team · · updated
Looking for an alternative to FirmaEC? firmar.ec signs PDFs with your
.p12electronic certificate directly in the browser: no Java to install, no downloads, and it works on your phone too, with no app to download. It is free and open source. Signing happens 100% on your device and carries the same legal validity as FirmaEC, as long as your certificate is issued by an Information Certification Entity (ECI) accredited by ARCOTEL.
firmar.ec is not FirmaEC
Worth clarifying, because the names look alike: firmar.ec and FirmaEC are different tools.
- FirmaEC is the official signing app from MINTEL (Ministry of Telecommunications). You download and install it: the desktop build runs on Java, and there is a native Android / iOS app.
- firmar.ec is an independent, open-source, non-profit web app by IDK Manager. There is nothing to install: it opens in the browser.
It does not replace FirmaEC for everything —below you’ll see when you do need FirmaEC— but for the most common case (signing a PDF quickly) it removes the friction of installing software.
Why look for a FirmaEC alternative?
The most common reasons people look for another option:
- It requires Java. FirmaEC needs Java JRE 8+ installed; on many machines that’s an obstacle (versions, permissions, antivirus).
- On mobile it caps at 4 MB and requires installing an app. FirmaEC has had a mobile app since August 2022 (v2.11.0, Android 8.0+ and iOS 12+), but it accepts documents up to 4 MB, against the 512 MB of its desktop build (official changelog; retrieved 23 August 2026).
- You can’t install software. On a corporate, hotel, or internet-café machine you often lack install permissions.
- You just need to sign one PDF fast and don’t want to install anything for a one-off.
What firmar.ec solves
| firmar.ec | FirmaEC | |
|---|---|---|
| Platform | Web (any browser) | Java desktop + native Android / iOS app |
| Installation | None | Desktop: Java JRE 8+ + token driver. Mobile: app from the store |
| Mobile (iOS/Android) | ✅ Yes (PWA, nothing to install) | ✅ Yes (native app from the store) |
| Maximum document size | 50 MB on any device | 4 MB on mobile · 512 MB on desktop |
Sign with .p12 | ✅ Yes | ✅ Yes |
| Cost | Free | Free |
| Open source | ✅ Yes (AGPL-3.0) | ✅ Yes (MINKA gob.ec) |
| Private key to a server | ❌ Never | ❌ Never |
See the full firmar.ec vs FirmaEC comparison →
When you do need FirmaEC (not firmar.ec)
Let’s be honest: firmar.ec doesn’t cover everything. Use FirmaEC (or the matching official flow) if you:
- Sign SRI electronic tax documents, which require the XAdES format — firmar.ec today only does PDF (PAdES).
- Have a USB cryptographic token and need to sign with it (firmar.ec uses the
.p12file, not the physical token).
For everything else —signing a PDF with your .p12, from any device, with no install— firmar.ec is the direct web alternative.
Get started
Open app.firmar.ec or go to firmar.ec sign, load your PDF and your .p12 certificate, and sign. Nothing is uploaded to any server: your key never leaves the browser. If you received a signed PDF and want to confirm it’s valid, use the verifier.