Converting Data Types

Notion formulas can only return data of a single type. For reference, Notion formulas work with seven distinct data types:

• String
• Number
• Boolean (Checkbox)
• Date
• List
• Person
• Page

Additionally, you can only compare data that share the same type when you use comparison operators such as equal, and, or larger (and some require a specific data type).

Therefore, you’ll often need to convert data from one type to another in order to get your formula to work.

Here are all the methods you can use to convert data to another type.

Converting Strings

To numbers:

Function/Method	Example
toNumber	toNumber("42")

To Booleans:

Function/Method	Example
if	if(prop("Text") == "true", true, false)

Good to know: You can’t truly convert strings, numbers, or dates to Boolean values. What you can do is write a simple statement that outputs a Boolean true/false value using your starting piece of data as criteria.

Converting Numbers

To strings:

Function/Method	Example
format	format(42)

To Booleans:

Function/Method	Example
if	if(prop("Num") == 42, true, false)

To dates:

Function/Method	Example
fromTimestamp	fromTimestamp(prop("Num"))

Note: fromTimestamp only works if its argument is a valid Unix timestamp.

Good to know: replace, replaceAll, and test are able to automatically convert numbers and Booleans (but not dates) to strings. Manual type conversion is not needed.

Converting Booleans

To strings:

Function/Method	Example
format	format(true)

To numbers:

Function/Method	Example
toNumber	toNumber(true)
unaryPlus (+)	+true

Converting Dates

To strings:

Function/Method	Example
format	format(now())
formatDate	formatDate(now(), "MMM DD YYYY")

To numbers:

Function/Method	Example
timestamp	timestamp(now())
toNumber	toNumber(now())
minute	minute(now())
hour	hour(now())
day	day(now())
date	date(now())
month	month(now())
year	year(now())

Good to know: the toNumber function converts dates to their Unix timestamp, just like the timestamp function.

To Booleans:

Function/Method	Example
if	if(prop("Date") == now(), true, false)