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Even the Big Guys Get Validation Wrong

May 13th, 2004

I ordered a computer for someone from Dell last night. When I got to the end of the order, I mistyped a digit on the credit card number and the form was redisplayed with an “invalid credit card number” error. I added spaces between the digits (as they appear on the card) to check the number. Sure enough, one digit was wrong. I re-submitted, but the “invalid card number” error remained. I was sure the card was valid and that I typed in the correct number. After a little experimenting, it turns out that the order form could not handle the spaces that I added. The person I was ordering the computer for was looking over my shoulder and said that he would have never figured out to remove the spaces. I wonder how many people enter their credit card numbers as XXXX XXXX XXXX XXXX, just as it appears on the card.

(P.S. Dell seems to be a master at “Do you want fries with that?”)

categories Usability, Web Design
tags input-filtering, input-validation, Usability

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4 Responses to “Even the Big Guys Get Validation Wrong”

  1. #1 Enric Naval responds...
    November 8th, 2004 at 10:53 am

    This can be solved by puting a small example entry besides the text area. The users would see a text like:
    Example: XXXXXXXXXXXX (all numbers, no spaces)[
    When users encounter the problem, they will read the small example text and remove the spaces to make their entry as similar to the example as posible.

    This is many times easier than checking and correcting every single possible way a user can enter the data (users can be very imaginative when it comes to mangling input data].

  2. #2 Enric Naval responds...
    November 8th, 2004 at 10:54 am

    Ejem, let’s try a smaller text size.

    Example: XXXXXXXXXXXX (all numbers, no spaces)

  3. #3 Michael responds...
    May 1st, 2007 at 10:01 am

    I just type it in slowly and dont put in spaces cause of that error.

    Its one of those things, dont get too caught up in not making errors. If you do go back and correct it, but check your work over slowly the first time.

  4. #4 James Benson responds...
    July 1st, 2008 at 6:32 pm

    Most the sites I’ve seen do not replace spaces, how hard can it be.

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