Calculate Calendar Sum

If you’ve got a list of calendar dates and want to add them up in a meaningful way, the Calculate Calendar Sum Tool has you covered. It converts each date into a day number and totals them, giving you flexible output options like total days, weeks plus days, or approximate months.

Paste your input above or import a file below.
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Supported file types: .txt, .csv, .log
Total items: 0
Options
Skip invalid dates

How to Use:

  1. Enter one date per line into the Input Dates box. You can use formats like YYYY-MM-DD, MM/DD/YYYY, or similar.
  2. You can also import a .txt, .csv, or .log file using the Choose File button.
  3. In the Options box, choose how you want to see the result:
    • Total days adds up the day values as a raw sum.
    • Weeks + days breaks the total down into full weeks and leftover days.
    • Approx. months estimates total time in months (based on average days/month).
  4. Enable Skip invalid dates to ignore lines that don’t match valid date formats.
  5. The Calculated Output will update instantly as you type or change settings.
  6. Use Copy Output or Export to File to save the result.
  7. Click Clear All to reset everything and start fresh.

What Calculate Calendar Sum Tool Can Do:

This tool treats each date as a distance from the Unix epoch and adds their values together. It’s not measuring the span between dates instead, it adds each one’s absolute day value. The result can be viewed as total days, converted into weeks and days, or approximated in months. You can ignore invalid dates with a toggle, and the output updates in real time.

Example:

Input:

2024-01-01
2024-01-02
2024-01-03

Output (format: Weeks + days):

86771 week(s) and 6 day(s)

Common Use Cases:

This is great for exploratory analysis, converting dates into time-based metrics, or estimating long-term totals across datasets. For example, if you’re working with event dates, historical logs, or planning projections, this tool helps you sum those values in a fast, flexible way.

Useful Tools & Suggestions:

Once you’ve run the calculation, Convert Unicode to Decimal is useful if you’re dealing with numbers stored as Unicode characters. And for double-checking what each symbol represents, Name Unicode Symbols gives you a clear breakdown.

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