Verizon vs AT&T iPad 2 plans: Which is cheaper?

NEW YORK (CNNMoney) -- If you are getting the iPad 2, are you confused about what data plan is right for you?

You're not alone. Trying to figure out how much you'll pay doesn't require a degree in advanced mathematics, but it could help. That's because there are a total of eight different AT&T (T, Fortune 500) and Verizon (VZ, Fortune 500) plans that you can choose from, each with a different set of data caps and overage charges.

You'll probably save money with AT&T if you use a little data each month, and you'll save money with Verizon if you use a lot of data. But it's not that simple.

Determining how much you'll pay depends heavily on how much data you think you'll use. Go over that limit, and you could be shelling out a lot, depending on your plan. (For a comprehensive view of how much you'll pay per quarter-gigabyte, click here to open a spreadsheet we've compiled.)

The trouble is that determining how much data you'll need is an inexact science. A data plan with a 250 megabyte cap gets you about 1,300 Web pages, 400 photo downloads, 60 songs, 14 YouTube videos, or about an hour of Netflix videos. A 1 gigabyte plan gets you 6,500 Web pages, 2,000 photos, 300 songs, 65 YouTube videos or between three and six hours of Netflix viewing.

But how often will you be using the network and how often will you be on Wi-Fi, which doesn't count against your data usage? Who counts how many Web pages they visit each month?

Okay, take a deep breath, and we'll try to help you sort through this mess.

What are the plans? Unlike the original iPad, the iPad 2 with 3G will be available on either AT&T or Verizon.

AT&T offers two different kinds of plans: prepaid and postpaid. Both plans charge $15 for each 250 megabytes you use per month, or $25 for the first 2 gigabytes.

With the prepaid plan, AT&T makes you shell out money before the start of each month, and the network simply charges your credit card anew each month or each time you go over your data limit. So 251 megabytes costs $30 and 2.1 gigabytes costs $50.

The postpaid plan charges you once a month, and AT&T assesses a $10-a-gigabyte overage charge in excess of 2 GB. So 251 megabytes still costs $30 but 2.1 gigabytes costs just $35.

Verizon's plan is simpler at first blush. It doesn't offer a pre-paid plan. It offers postpaid plans in four different tiers: 1 GB for $20, 3 GB for $35, 5 GB for $50 and 10 GB for $80. A Verizon spokesperson said that as a customer gets close the upper end of the range in their plan, they get an alert that allows you to sign up for more service.(See correction below.)

What's the bottom line? If you know exactly how much data you'll be using, here are the cheapest plans:

For 250 MB of data a month or less, AT&T offers the cheapest plans by $5 a month. Between 250 MB and 1 GB, Verizon's plan will save you $5 a month over AT&T. From 1 GB to 2 GB, AT&T's plans are $10 a month cheaper than Verizon.

Between 2 GB and 4 GB is where it starts to get a little tricky: AT&T's postpaid plan and Verizon's plan cost the same for that range. But AT&T's prepaid plan will cost a lot more. If you go with AT&T, the postpaid plan could save you $15 a month over the prepaid plan.

Here's where it gets easy though. Anything over 4 GB is clearly Verizon's territory. If you're enough of a data hog that you're using 10 GB a month, Verizon will save you at least $25 a month.

Now, if you are unsure of how much you'll be using and reluctant to pay up if you go over your limits, it's a whole different ball game. A Verizon customer with a 1 GB plan who accidentally uses 1.1 GB of data would pay $15 a month more than an AT&T customer. Similarly, a 250 MB AT&T customer that uses 251 MB would pay $10 a month more than a Verizon customer.

Thoroughly confused? The good news is that Apple (AAPL, Fortune 500) doesn't make you enter into a contract with Verizon or AT&T. So if your plan isn't working out, you can always cancel it or switch your plan (within the same carrier of course) each month.

Correction: CNNMoney originally reported that there were overage charges for Verizon's iPad 2 data plan. A Verizon spokesperson later clarified that this is not the case.