I have a field named "ZIP" which has the zip code information for numerous records. Some of them have 9 numbers, but I only want them to have the first 5. What should my Pre-Logic Script look like to Field Calculate removing the last 4 numbers in this field?

Here is an image of the Field Calculator and the field:

enter image description here

  • In python you can use the simple expression: !ZIP![0:4]. No code block necessary. – Jyler Apr 13 '16 at 16:23
  • I agree, but this is giving me a geoprocessing error. – forrestchev Apr 13 '16 at 16:44
  • Got your radio button switched to Python? Also, don't include that period after the ]. – Jyler Apr 13 '16 at 16:45
  • Yes and I did not include the period. – forrestchev Apr 13 '16 at 16:49
  • 1
    Is ZIP a field alias by chance? Or conversely, you might disable your code block. – Jyler Apr 13 '16 at 17:57

If the field is numeric, Python expression:


will fail.

It is easier to use vb script option:


This will populate output field of numeric and text type.

  • That's it! It is not a string, so that python expression does not work. Thanks! – forrestchev Apr 13 '16 at 20:24
  • It will work with some modification, e.g. if output field is numeric it's going to be float(str(!ZIP)[:4]) – FelixIP Apr 13 '16 at 20:30

Use the string indices. Instead of creating a whole function, just do something like:

!ZIP![:5] --> basically grab everything from 0 index up to but not including the 5th index.

So it only grabs the indices 0,1,2,3,4.

Check out this tutorial for more information.

If there are more than 5 it will just grab the first 5. If there are 5 exact, it will grab them.

  • 2
    in the field calculator it'll probably be something like !ZIP![:5] I think – Midavalo Apr 13 '16 at 18:28

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