Randomisation

[Nick_Bettes]

How can I generate a random number to go into a custom field?

[Jeff_Arnold]

You need to use a third party application to do that.
Something like Zapier or Integromat.

[Nick_Bettes]

I have just updated each contact with a couple of random numbers and dates from Excel. Allows me to split contacts and throttle sends etc. - desn’t matter that they are static.