Open-source election counting
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
RunasSudo e825ca1491
Update for Rust 1.62
2 months ago
docs Update documentation 4 months ago
homepage Update documentation 4 months ago
html Use "ballots" consistently vs "ballot papers" 6 months ago
src Update for Rust 1.62 2 months ago
tests Autodetect when to normalise ballots, remove explicit --normalise-ballots 6 months ago
.gitignore Update documentation 4 months ago
COPYING Initial commit 1 year ago
Cargo.lock Update wasm-bindgen 4 months ago
Cargo.toml Update for Rust 1.62 2 months ago Rename docs files to avoid reserved Windows paths 9 months ago Implement constraint matrix logic and test case 1 year ago Don't reapply wasm-bindgen/wasm-opt if no changes 1 year ago Update rustfilt path 11 months ago Add code coverage calculation 1 year ago
test.csp Add subcommand for BLT/CSP file conversion 1 year ago


OpenTally is an application for counting various preferential voting elections, with an academic focus, and emphasis on configurability.

OpenTally may be used in a number of different ways:

  • as an online web application, no installation or special software required
  • as a standalone command line application
  • as a Rust library within another application


OpenTally accepts data in the BLT file format, and can count votes using:

OpenTally is highly customisable, including options for:

  • different quotas and quota rules (e.g. exact Droop, Hare)
  • calculations using fixed-point arithmetic, guarded fixed-point (quasi-exact) or exact rational numbers
  • different tie breaking rules (backwards, random, manual) with auditable deterministic random number generation
  • multiple constraints (e.g. affirmative action rules)
  • equal rankings

Online usage

See the quick start guide for how to use OpenTally online.

Command line usage

OpenTally may also be invoked as a command line application. Run ./opentally --help to view help.

For example, run ./opentally stv path/to/blt_file.blt --ties backwards random --random-seed foobar.