hi @RJ_Southam,
Your formula is correct as long as the field with the date of birth is called DOB.
I would possibly modify it to this: If(DOB<=12/31/2017, :star: ,"") if you want to actually have a blank field when the condition does not hold instead of a field with a space.

Hope this helps!

Website: alessiomonino.com
Calendly: Calendly - Alessio Monino
Email: alessio.monino@gmail.com

Thanks Alessio, any other idea it still says invalid formula I tired =< and <= I also tried brackets around the date…

IF(
  DATESTR({DOB}) <= "2017-12-31",
  "star"
)

Actually the original formula had several issues.

• Emoji are characters and need to be enclosed in straight quotes.

• Hardcoded date strings need to be enclosed in straight quotes. As written 12/31/2017 is a mathematical expression that evaluates to about 0.000191917091816.

• It is also better to compare text strings with text strings rather than hoping that Airtable will correctly do data type conversion.

• it is better to completely omit the third parameter than to include a text string of one space or an empty text string.

IF(
  DATESTR({DOB}) <= "2017-12-31",
  "star"
)

Thank you that worked!

IF(
  DATESTR({DOB}) <= "2017-12-31",
  "star"
)

Would you help me with a second part I want to flag children that are turning 3 this year as of today.
IF(
DATESTR({DOB}) <= “2017-12-31”,
“ :mortar_board: ”,IF(
DATESTR({DOB}) between today and “2019-12-31”, :balloon:
)