Electoral system calculator
Calculator finds out number of seats in parliament using D'Hondts method.

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Calculations data - electoral thresholds

Number of seats to assign
Threshold for single party%
Threshold for coalition%

Calculations data - votes

Name of the political optionNumber of votesTick-up in case of coalitionVotes as percentage [%]Above electoral threshold
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Result - seats in parliament

Total number of votes0
Assigned seats in parliament

    Some facts

    • In parliamentary republic, citizens vote for their representatives, who then represent them in parliament.
    • In the proportional system, the composition of the post-election parliament should reflect social groups among voters.
    • The bigger group means more representatives in parliament.
    • The D'Hondt method is an algorithm of allocating seats based on votes distribution.
    • The algorithm of the D'Hondt method is as follows:
      • 1. We remove groups that did not exceed the electoral threshold. For example, the threshold in Poland (as of 2019) is 5% for single parties and 8% for coalitions.
      • 2. For each committee, we calculate successive weights by dividing the number of votes by successive natural numbers from 1 to the total number of seats to be filled in (for example the polish parliament has 460 seats):
        wi=Liw_i = \frac{L}{i}
        where:
        • wiw_i - i-th weigh for given committee,
        • LL - number of votes received by given committee,
        • ii - consecutive natural numbers from 1 to the total number of seats to be filled.
      • 3. We put all weights (with committees) on one list sorted in descending order.
      • 4. We select n first entries from the list until all seats are assigned.
    • ⓘ Example: Four committees A, B, C, D took part in the election. The number of seats to be filled to 8. The electoral threshold is 5%. The committees received successively:
      • A - 720 votes (46.15%),
      • B - 300 votes (19.23%),
      • C - 480 votes (30.77%),
      • D - 60 votes (3.85%).
      Using the D'Hondt algorithm we get:
      • 1. Committee D did not exceed the 5% electoral threshold. Committees A, B and C go to further steps.
      • 2. We divide number of votes by successive natural numbers from 1 to 8. We get the following weights:
        • committee A: 720, 360, 240, 180, 144, 120, 102, 90,
        • committee B: 300, 150, 100, 75, 60, 50, 42, 37,
        • committee C: 480, 240, 160, 120, 96, 80, 68, 60.
      • 3. We place the received weights on one descending sorted list and select the first 8 committees:
        • 1. 720 A,
        • 2. 480 C,
        • 3. 360 A,
        • 4. 300 B,
        • 5. 240 A,
        • 6. 240 C,
        • 7. 180 A,
        • 8. 160 C.
      • The number of seats won by given committees are:
        • committee A won 4 seats,
        • committee B won 1 seat,
        • committee C won 3 seats,
        • committee D has no any seats, because, it did not exceed the electoral threshold.

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