2015 resolution: kill maxlength, add validation

If you’re still looking for a New Year’s resolution, here’s a suggestion:

Go over all your UI code now, and whenever you see something like this…


<input id="credit-card-number" maxlength="16">

… please spend a few minutes to remove maxlength and add some real validation code instead.

Why? Because in 2015, I think it’s reasonable to expect any UI to be flexible enough to handle user input even with a few extra characters.

Your users should be able to copy&paste their credit card number from a Google Doc to your form, with or without dashes and blanks. Leading/trailing whitespaces should be handled gracefully. Just remove all those extra characters before validation - seriously, it’s probably one line of code.

Entering a phone number with or without brackets should just work. Including international numbers. A maxlength=”10” for phone numbers is just ridiculously inconvenient.

Copying an order/tracking/customer number from an email to a support request form should just work and not require the user to manually un-group numbers in a text editor first.

Come on, this is 2015. Just do it.

Happy New Year!

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Written on December 28, 2014.