I have a 4 digit postcode, I have to look it up every time I have to fill in an address form for delivery.
I've had people screw 1 digit up in that postcode and their items (a laptop in one case) went to the completely wrong city.
A code sounds foolproof, until you realise most people don't engage with them for most of their lives - you don't tell the uber driver the zip/post code you are waiting in, and travelling to, nobody does.
edit: just to add - Magic numbers are bad. Software engineers know that a number that's undocumented in code is unmaintainable, a zip code is worse.
> I have a 4 digit postcode, I have to look it up every time I have to fill in an address form for delivery.
> A code sounds foolproof, until you realise most people don't engage with them for most of their lives - you don't tell the uber driver the zip/post code you are waiting in, and travelling to, nobody does.
When the above comments said +4, they meant knowing the second half of the nine digit zip code.
Basically everyone in the US knows the first 5 digits. It's really easy to memorize them. If you can remember your city, you can remember your zip code. And in the US you use it all the time, so it stays memorized.
> edit: just to add - Magic numbers are bad. Software engineers know that a number that's undocumented in code is unmaintainable, a zip code is worse.
That complaint about magic numbers is completely off base. Magic strings are just as bad in software. "Beverly Hills" and 90210 are equal sins on the magic front.
> Basically everyone in the US knows the first 5 digits. It's really easy to memorize them. If you can remember your city, you can remember your zip code. And in the US you use it all the time, so it stays memorized.
What's the 5 digits for Yonkers New York (edited because I originally had NYC)
> That complaint about magic numbers is completely off base. Magic strings are just as bad in software. "Beverly Hills" and 90210 are equal sins on the magic front.
For the same reasons, that's why it would be: Beverly Hills, Los Angelos County, California, USA, 90210
> What's the 5 digits for Yonkers New York (edited because I originally had NYC)
Nobody sends packages where the destination is an entire city. If someone gives me an address inside Yonkers, it'll have the zip code in the address. I've never had to look up a zip code in my life.
> For the same reasons, that's why it would be: Beverly Hills, Los Angelos County, California, USA, 90210
Which reasons? That has nothing to do with magic numbers, except that a 'magic full mailing address' is still bad, you don't shove that into the middle of your code either. If you're looking at the "made a typo" reason then that's where showing the address after putting in the zip code will give you the same verification but faster.
Your zip plus 4 changes. It isn't worth trying to know as it isn't supposed to be constlnt. If you send a lot of mail there is a discount for using it but you have to update everyone's address often (iirt at least 4x per year)
Source? The numbers correspond to the USPS distribution centers and carrier routes. If the numbers are changing that would imply an increase in zip code subdivisions, making each zip code a better address predictor for a given individual.
This is a bad hill to die on for a ux conversation. "10% can feel kind a big number when 100% is huge" is a funny argument, as is trying to be pedantic about "nobody knows" as a shortcut for "most people won't know and you can't rely on any particular user knowing". If 10% is big enough to matter I can't wait to tell you about 90%!
I'm not suggesting that one would design for the 10%, but I also think that writing off 10% - "nobody" - (particularly of a large number of people) is pretty dumb too.