Do the weights need to add to 100?

No. Any nonnegative proportional weights work because each is divided by the total weight.

Will allocations add exactly to the total?

The underlying values do. Display rounding can create a small visible difference in the last decimal places.

Does this allocate whole seats or units?

No. It returns continuous values and does not apply an integer apportionment method.

Can one recipient have zero weight?

Yes. That recipient receives zero allocation, provided at least one other weight is positive.

Apportionment Calculator

Apportion a total amount among four recipients in proportion to their weights and review each recipient's percentage share. Review the assumptions and supporting outputs before using the result.

Total Amount to Apportion

Recipient A Weight

Recipient B Weight

Recipient C Weight

Recipient D Weight

Recipient A Allocation

40,000

Recipient B Allocation: 30,000
Recipient C Allocation: 20,000
Recipient D Allocation: 10,000
Recipient A Share: 40

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Works with WordPress, Webflow, Squarespace, Wix, Framer, Shopify, and any website that supports custom HTML or iframes.

Allocations sum to the total before display rounding. Percentage share shows each weight's proportion of the combined weight.

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How to Use This Calculator

Enter the total amount and a nonnegative weight for each recipient. Weights may be percentages, counts, scores, usage, population, or another consistent basis.

Formula & Methodology

Each allocation equals total amount multiplied by the recipient's weight divided by the sum of all weights.

Worked example

Apportioning 100,000 with weights 40, 30, 20, and 10 produces allocations of 40,000, 30,000, 20,000, and 10,000.

This calculator performs continuous proportional allocation. It does not implement legislative seat methods, divisor methods, largest-remainder rules, minimum guarantees, caps, integer rounding, tax apportionment statutes, or legal allocation rules.

General allocation tool only. Use the specific statutory, contractual, accounting, electoral, or policy method required for the real decision.

Related Guides

How Proportional Apportionment Works
Calculate proportional seat or unit allocation from population or weight data. Understand the Hamilton, Jefferson, and Webster apportionment methods and where each is used.

Frequently Asked Questions

Do the weights need to add to 100?: No. Any nonnegative proportional weights work because each is divided by the total weight.
Will allocations add exactly to the total?: The underlying values do. Display rounding can create a small visible difference in the last decimal places.
Does this allocate whole seats or units?: No. It returns continuous values and does not apply an integer apportionment method.
Can one recipient have zero weight?: Yes. That recipient receives zero allocation, provided at least one other weight is positive.

Published 8/20/2026