D21 – Janeček method

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Single-winner methods Single vote - plurality methods First preference plurality (FPP) Two-round (US: Jungle primary) Partisan primary Instant-runoff UK: Alternative vote (AV) US: Ranked-choice (RCV) Party block voting Plurality block voting Condorcet methods Condorcet-IRV Round-robin voting Minimax Schulze Ranked pairs Maximal lottery Positional voting Plurality (el. IRV) Borda count (el. Baldwin, Mdn. Bucklin) Antiplurality (el. Coombs) Cardinal voting Score voting Approval voting Majority judgment STAR voting
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The D21 method, also known as the D21 – Janeček method or Democracy 2.1, is an electoral system applicable for both single-winner and multi-winner voting, which allows voters to cast more votes than there are open seats. It is a cardinal method like approval voting and combined approval voting. The method was developed by Czech mathematician Karel Janeček.

This voting method has yet to be used in any general elections. It has been used in several participatory budgeting programs conducted by various cities.