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Version: 1.0

📅 Add/Subtract Date Calculator – User Guide

This tool allows you to add or subtract specific time periods (years, months, weeks, days) from a starting date to find a new resulting date. It’s useful for planning events, deadlines, age projections, and more.


🧭 Modes

Make sure the "Add/Subtract" tab is selected (next to “Count Days”).


📥 Input Fields

1. Start Date

  • Set the base date from which the calculation will begin.
  • Example: 10/15/1986

2. Operation Selector

  • Choose either:

    • Add: Move forward in time
    • Subtract: Move backward in time

3. Duration Entry

  • Enter the time you want to add/subtract:

    • Years
    • Months
    • Weeks
    • Days

You can use any combination of these units.

4. Holidays (Optional)

  • Expand to configure if specific holidays should be excluded (if applicable).

▶️ Calculate Button

Click the “Calculate” button to apply the operation and generate the result.


📊 Result Display

You’ll see:

  • A calendar view showing:

    • The Start Date
    • The Resulting Date
  • Labeled as:

    • From [Start Date]
    • To [Calculated Date]

📝 Example

Input:

  • Start Date: 10/15/1986
  • Operation: Add
  • Years: 36

Output:

  • To Date: 10/15/2022

✅ Use Cases

  • Project scheduling
  • Retirement or age projection
  • Deadline planning
  • Historical or future date offsets
  • Duration-based legal or academic calculations