Verifiable online voting system

To set up an election, you may simply use our voting platform.

Belenios aims at providing an easy to use voting system, guaranteeing state-of-the-art security, namely vote privacy and verifiability. It can be used in many types of elections (including referendums), ranging from scientific councils to sport associations.

  • Vote privacy: no one can learn the vote of a voter. Vote privacy relies on the encryption of the votes.
  • End-to-end verifiablity: Every voter can check that her vote has been counted and only eligible voters may vote. End-to-end verifiablity relies on the fact that the ballot box is public (voters can check that their ballots have been received) and on the fact that the tally is publicly verifiable (anyone can recount the votes). Moreover, ballots are signed by the voter credential (only eligible voters are able vote).

Multi-languages hosted on Weblate


Belenios is available in a few languages for voters and for the administrator of the election. We need you help to pursue this effort. We have hosted our translation files on weblate. You can easily create an account and contribute. We have written a few guidelines on how to best translate Belenios. Your help will be very valuable to our project!

Release of Belenios 1.12


The main change is a bug fix: some users reported that they were blocked when voting. This was due to a bad interaction with some browser extensions. This is now corrected.

Security analysis of Belenios (in French)


We provide a security analysis of Belenios, mainly w.r.t. the criteria defined by the CNIL (Commission Nationale de l'Informatique et des Libertés). Since these criteria are somewhat specific to French regulations, the document is written in French. It can be found here.

Release of Belenios 1.11


One important feature of the new release is that the main page of the election now includes verification material for election authorities and voters. In particular, the number and names of decryption trustees are displayed as well as a hash of the voter list and all public and verification keys. The instructions on what to check and how are spelled out here (or here for the French version) for each party (trustees, electoral commission, credential authority, administrator, voters).
Moreover, in case no credential authority is used in an election (which reduces the security level of the election), then the administrator can now save the list of private credentials before starting the election. This allows the administrator to resend a credential to a voter that has lost it.

Release of Belenios 1.10


We have added mixnets to Belenios. What does this mean? You can now organize any type of elections, e.g. where voters rank candidates by order of preference or provide a grade. In the mixnet mode (still experimental), the raw ballots are provided at the end of the election, in a random order, to protect privacy. You can then apply your favorite counting methods (e.g. STV, Condorcet, or majority judgement) to compute the winner. More information on how to use Belenios for alternative voting can be found here. Note that Belenos still supports the previous homomorphic mode, which is more convenient (and efficient) in case of elections where voters simply select some number of candidates among a list.
The new version also includes minor changes in the administration interface, to help setting up an election with trustees.

Release of Belenios 1.9


Belenios 1.9 now includes the possibility to temporarily hide the result from the public (e.g. to delay the announcement of the winner). We have also fixed some bugs.

Release of Belenios 1.8


The new version 1.8 of Belenios includes two main changes.

  • To use our platform as an election administrator, you may now create an account online (select public mode).
  • The threshold encryption mode is now fully integrated to our platform. For example, the decryption key may be split among 3 authorities such that 2 suffice for decryption, as recommanded by the CNIL. Any other combination can be chosen of course.

Release of Belenios 1.7


The main visible change of Belenios 1.7 is that elections can now be archived and/or deleted, according to our policy regarding data management (click here for the French version). In particular, all elections will be deleted after one year. An archive of the election may be previously saved by the administrator of the election.

Release of Belenios 1.6


This new version of Belenios includes changes mandated by the new GDPR regulation.
The explanations given on the web interface for setting an election have been improved thanks to users comments.

Release of Belenios 1.5


Belenios 1.5 has been released and integrated to our voting platform. It is now possible to set the server as one of the trustees in charge of the decryption keys. Note that supported languages are now English, French, German, Italian, and Romanian.
Since its launch, Belenios has been used to organize about 200 elections and more than 6000 ballots have been cast.

Fully open voting platform


Our on-line voting platform can now be easily used to set up an election by login using your Google account (or the INRIA CAS server).

Multi language available


Voters can now vote in their favorite language (among English, French, and German). More languages to come soon! If you need another language for an important election, you may also contact us.

Code release


The latest version of our Belenios software is available. With this sofware, you may run an election on your own server. Belenios is distributed under the terms of the GNU Affero General Public License version 3.

Online platform


The first release of our on-line platform is up. No need to install software anymore. You can set up an election simply through our interface. Note however that this interface is still under development. Therefore the access is granted through the INRIA CAS server or on request. Stay tuned for the release of our fully open voting platform! To learn about the new developments of Belenios, you may subscribe to our mailing-list.