Build a Parliament.
Set the votes. Choose the parties. See the path to a majority.
A mathematical majority tells you about seats. It does not predict an agreement to govern.
Jump to your resultSet your scenario
Choose a starting point, then adjust the inputs.
Using 2026 electorate and nomination rules.
“Make total 100%” rescales every share in the same proportion.
Electorate rules & scenario limits
“Other” is an aggregate of separate minor parties and cannot qualify collectively. Split any potentially qualifying minor party into its own record before modelling. For 2026 scenarios, TPM is capped at one additional list candidate following the official nominations; the 2023 preset uses its historical lists. Other parties are assumed to have sufficient candidates.
Electorate inputs are assumptions, not forecasts. The forecast preset uses mean vote shares; this calculator does not reproduce the full seat distribution. See probabilistic results.
Official Sainte-Laguë rules · 5% party vote or an electorate win. Independent winners reduce the proportional seat pool.
Choose a combination
Select the parties you want to add together.
Party combinations show seat arithmetic only. Opportunity is included only when you select it.