# start

Learn how to use the start function in Notion formulas.
The `start()` function returns the start date from a date range. It accepts a single date argument.
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start(date)
`start()` is useful for obtaining the start date from a Date property which contains a date range.
When you pass a single date as the argument - i.e. from a Created Time/Last Edited Time property, or a timestamp - `start()` simply returns that date.

## Example Formula

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// Assume a property "Date" exists, with
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// a row value of June 23, 2022 → June 27, 2022
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start(prop("Date")) // Outpuut: June 23, 2022

### Date Math within start() and end()

It’s useful to note that date math functions like dateAdd and dateSubtract return a date object that does not contain a date range - even if their argument does include one.
When these functions are passed a date object that includes a range, they only use a start date.
For this reason, the following two formulas will return the exact same date:
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// Assume a property "Date" exists, with
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// a row value of June 23, 2022 → June 27, 2022
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start(dateAdd(prop("Date"),30,"days")) // Output: July 23, 2022
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end(dateAdd(prop("Date"),30,"days")) // Output: July 23, 2022
Therefore, you must use the end function within your date math function if you wish to operate on the end date in a date range:
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// Assume a property "Date" exists, with
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// a row value of June 23, 2022 → June 27, 2022
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dateAdd(end(prop("Date")), 30, "days") // Output: July 27, 2022

## Example Database

The example database below counts the number of days in a date range.

### "Days" Property Formula

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// Compressed
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dateBetween(end(prop("Date Range")), start(prop("Date Range")), "days")
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// Expanded
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dateBetween(
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end(
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prop("Date Range")
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),
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start(
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prop("Date Range")
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),
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"days"
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)
This example formula uses `start()` and end to pass beginning and ending arguments to the dateBetween function.
By specifying "days" as the third argument, we get the number of days in the date range.