Insurance underinsurance clause arithmetic calculator

Calculate required cover and proportional payment before deductible with your own figures.

Your numbers

Use the units shown. Results update as you change valid inputs.

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Use required cover and proportional payment before deductible to compare changes to your inputs. The method and limits below explain the scope.

Examples

Examples

Try the starting example

Property value (USD)
200000
Required insured fraction (%)
80
Actual cover (USD)
100000
Covered loss (USD)
40000
Deductible (USD)
1000
Required cover (USD)
$160,000.00
Proportional payment before deductible (USD)
$25,000.00
Net worksheet payment (USD)
$24,000.00

Try another scenario

Property value (USD)
200001
Required insured fraction (%)
80
Actual cover (USD)
100000
Covered loss (USD)
40000
Deductible (USD)
1000
Required cover (USD)
$160,000.80
Proportional payment before deductible (USD)
$24,999.88
Net worksheet payment (USD)
$23,999.88
Calculation method

Calculation method

Required cover (USD)

Average-clause example: loss × min(1,cover/required cover), capped by cover and reduced by entered deductible.

Proportional payment before deductible (USD)

Average-clause example: loss × min(1,cover/required cover), capped by cover and reduced by entered deductible.

Net worksheet payment (USD)

Average-clause example: loss × min(1,cover/required cover), capped by cover and reduced by entered deductible.

Symbols and units
a
Property value (USD)
b
Required insured fraction (%)
c
Actual cover (USD)
d
Covered loss (USD)
e
Deductible (USD)

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions & limits

Assumptions & limits

  • User-supplied measurements and assumptions; Average-clause example: loss × min(1,cover/required cover), capped by cover and reduced by entered deductible. Supported limits: Finite numeric values bounded to 1e9 magnitude; lists and tables contain 1–100 records unless a stricter bound is stated. Inputs use the units shown. Lists explicitly paired by a method must have matching lengths; independent polynomial coefficient vectors may differ. Respect stated physical, interpolation, policy and computational domain limits.
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