Formula for counting number of attachments

[Kenston]

I have a column of Attachment type. I want to create a formula based on the number of uploaded/attached files. How can I count the number of uploaded/attached files in that column?

[W_Vann_Hall]

This is a clever trick suggested by @Simon_Brown: Given an Attachment field {Attached}, the formula to count the number of attachments is

IF(
LEN({Attached}=0,0,
LEN({Attached})-LEN(SUBSTITUTE({Attached},",",""))+1)

This works because Airtable casts {Attached} as a comma-separated string of concatenated RECORD_IDs. The formula then compares the length of the string with the length of the same string with commas removed (plus 1, to make sure single attachments get counted).

[Kenston]

This workaround works! Thanks!

Just a little of syntax typo (missing closing parenthesis for first LEN):

IF(
LEN({Attached})=0,0,
LEN({Attached})-LEN(SUBSTITUTE({Attached},",",""))+1)

[W_Vann_Hall]

Thanks for the catch!

[Thomas_de_Beauc]

This formula gives wrong results when attachments have commas in the filename, here is one that doesn’t have this issue !

IF(Attachments = BLANK(), 0, (LEN(Attachments) - LEN(SUBSTITUTE(Attachments, "https://dl.airtable.com/.attachments/", ""))) / LEN("https://dl.airtable.com/.attachments/"))

Airtable nicely adds the download address to the comma-separated list of attachments of the Formula field, and "https://dl.airtable.com/.attachments/" is indeed much less likely to occur than innocent commas in a filename.

Credit and reference : Count multiple keywords in text - #3 by Karlstens