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JavaScript Genealogy Calculator © Copyright 1998 Larry Estep; Permission is granted to copy or mirror the JavaScript Genealogy Calculator (JVC) under the following terms. The existing Copyright statement is included in the JavaScript code...

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Enter two known values and press Calculate in the third box to determine the unknown value.

You MUST enable Script on your browser to use this facility

JavaScript Genealogy Calculator

Enter two known values and press calculate to determine the unknown value;
eg if you know age and death calculate birth; if know birth and death calculate age etc.

Purpose

The JavaScript Genealogy Calculator (JGC) was designed to assist Internet genealogists with important date conversions. This utility will calculate an unknown value for a date of birth, date of death or age at time of death, provided the user supply two of the known values.

The table below will summarize how the calculator works with your input.

You input	You input	JGC calculates
Date of Death	Age	Date of Birth
Date of Death	Date of Birth	Age
Date of Birth	Age	Date of Death

Help for the JGC - Help file for the JavaScript Genealogy Calculator -- Revised: 24 Mar 1998

Help for the JGC

Help file for the JavaScript Genealogy Calculator -- Revised: 24 Mar 1998

Selections:

Purpose

The table below will summarize how the calculator works with your input.

You input	You input	JGC calculates
Date of Death	Age	Date of Birth
Date of Death	Date of Birth	Age
Date of Birth	Age	Date of Death

Examples

Example 1

Vital records indicate that Ralph Smith died on August 4, 1857 at the age of 65 years, 3 months and 24 days.

Using the JGC, follow the steps below to determine his date of birth.

Under the Age column enter 65 for Years(s), 3 for Month(s), and 24 for Day(s).
Under the Date of Death column enter 8 for the Month, 4 for the Day and 1857 for the Year.
Under the Date of Birth column select the Calculate button to determine Ralph's Date of Birth.

In this example, Ralph was born April 11, 1792.

Note: Use four digits to represent years in JGC or you will experience problems.

Example 2

An obituary states the date of birth for Alexander Shoemaker as July 6, 1762 and the date of death as March 15, 1844.

Using the JGC, follow the steps below to determine his age at the time of death.

Under the Date of Birth column enter 7 for the Month, 6 for the Day and 1762 for the Year.
Under the Date of Death column enter 3 for the Month, 15 for the Day and 1844 for the Year.
Under the Age column select the Calculate button to determine Alexander's age at the time of death.

In this example, Alexander was 81 years, 8 months and 9 days at the time of death.

Known Bugs

The JavaScript Genealogy Calculator (JGC) is valid from 1583 to present date. Changes were made in 1582 that are not reflected in this work. For more information about calendar changes visit Leap Day.

Local Copies

Permission is granted to copy or mirror the JavaScript Genealogy Calculator (JVC) under the following terms.