Phone Purchase Cost Comparison Calculator

From the device price to the return conditions, compare the quotes you received on the same basis.

This calculator only computes the quote amounts you enter. It does not look up or judge subsidies, plan eligibility, or card spending requirements.

Enter the quotes to compare

Month 0 is the point of purchase, and the mobile service billing cycles start at month 1. If you change the period, check the charge segments again.

Calculation condition file

Saves the conditions you entered as a file on your own device and loads them back. The file is not sent to a server.

The quote name and notes are not saved; only the values used in the calculation are.

Only files saved by this calculator can be loaded. Loading overwrites what you have entered now.

Cost comparison results by condition

Comparison scenario

The two scenarios are calculated separately. They are not mixed on one screen to build a ranking.

Nothing has been calculated yet. Enter your quotes and press Compare costs by condition.

Monthly costs and end-of-term obligations

Once you calculate, the spending and cumulative amount for each billing cycle appear here.

How to compare on the same basis

  1. Set the comparison period. Match it to the contract term of the quote you received so that both quotes share the same basis.
  2. Enter the actual billed amounts written on the quote. Not the list price or the subsidy, but the amount you will pay.
  3. Split the timeline into segments at every billing cycle where the charge changes. Enter them in blocks such as months 1-6 and months 7-24.
  4. Put discounts with a condition attached, such as card spending requirements, into conditional discounts, and also enter the extra amount you spend to keep that condition.
  5. Check the device status after the end of the term and any additional settlement amount. Leave amounts you could not confirm as unknown, not as 0.

What this calculator does not do

  • It does not calculate prorated charges based on the activation date or early termination settlements. It compares by whole months only.
  • It does not automatically deduct the used value or the expected resale price of a device you return.
  • It does not automatically judge subsidies, plan eligibility, or whether card spending requirements are met.
  • It does not automatically deduct points and coupons as if they were cash. Enter only confirmed cash discounts as amounts and keep the other benefits as notes.
  • If the models differ, only the amounts are compared. That does not mean the performance or the value is the same.

Calculation rule version: -

Frequently asked questions

Is a SIM-free purchase always cheaper?
This calculator does not assume that any particular purchase method is always better. It compares the device price, charges, conditions, and end-of-term obligations you entered over the same period.
Is an unconfirmed cost treated as zero?
No. If an item is unconfirmed, it shows a partial subtotal of the amounts entered and withholds any judgment about the lowest option.
Should I also enter the spending needed for card requirements?
Enter separately only the extra spending required to meet that condition, not the whole amount you usually spend.
Can I compare an option that returns the device with one that keeps it?
You can view the amounts side by side, but because the device status at the end differs, they are not marked as the lowest option under the same conditions.