att deathstar icon 260x216 iPhone 4: Calculate Your Potential AT&T Bill Under Their New Pricing RulesIf you have an iPhone or iPad now, do not fret, you are safe. Under the sweeping changes that AT&T is enacting you can keep your current unlimited plan if you so desire. Then again, if you are a extremely light data user, you might want to downgrade.

Either way, let’s take a look at just what you could be spending if you had to use your iPhone under the new plans put forth today. After all, that is the only fair way to get a grip on just how good or not the new AT&T  plans are. Before that however, shame on Apple for pitching the iPad 3G at its launch with an unlimited data plan, and then reneging on it a few weeks later. While they are allowing current users to keep their plans, there are thousands of people who will purchase an iPad 3G expecting to be able to buy an unlimited plan who will not be able to do so.

Pull out your iPhone and head to Settings, then General, then Usage, and then scroll down to the Cellular Network Data section. Add the total sent and received data together to get the sum of your data usage on the device. Finally, look at the very bottom of the Usage screen, right below the Reset Statistics button to get the time from your last data reset.

If if has a set time frame, divide your data usage by that time to calculate your megabytes (or gigabytes) per month. If it says “Last Reset: Never,” then merely use the number of months you have had the phone for the time element. Last reset 3 months ago? Used 5 gigabytes of data? You are burning through 1.66 gigabytes per month, and so on.

Now, if you use less than 200 megabytes a month, you would qualify for the ‘DataPlus’ plan, which will run you $15 a month. If you use between 200 and 400 megabytes a month, you could still use the DataPlus plan, but it would run you $30 a month, at which point it is cheaper to upgrade to the DataPro level.

If you do burn fewer than 2 gigabytes per month, the DataPro plan will cost you $25 a month. AT&T claims that this fits 98% of all iPhone users. Extra bandwidth is $10 a gigabyte after that, which is less abusive than before.

But what about tethering? If you were sly and have had your iPhone hacked at any point in the past you may have taken advantage of tethering for free. AT&T will now let you tether, for a fee. For an additional $20 a month you can tether, and still pay the same rates for bandwidth. The AT&T announcement was ambiguous, but it seems that tethering is part of the same megabytes bucket as normal data usage. Do note, that if you decide to keep your current unlimited plan, you cannot buy the sanctioned AT&T tethering package.

Add up your usage and find your theoretical new price point. Are you tethering on the sly? What is your average consumption per month, do you have to add a gigabyte to the DataPro plan? When you are all set and done, does your bill go up or down? Personally I fit just under the 2 gigabyte per month level, so I could buy the DataPro and save $5 a month if I wanted, but will keep the old unlimited plan just in case.

And you?

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