Phone Plan Comparison Calculator
Compare two phone plans on monthly cost, data allowance, and features.
Returns annual savings and cost per GB to identify the better value mobile plan.
Phone plan comparison requires looking beyond the advertised monthly price to the total cost of ownership including device financing, taxes, fees, and overage charges.
True Monthly Cost Formula:
True Monthly Cost = Plan Cost + Device Payment + Taxes & Fees + Add-ons − Autopay Discount
Total Annual Cost:
Annual = True Monthly Cost × 12
Two-Year Total (standard comparison window):
24-Month Cost = True Monthly × 24 + Activation Fee − Promotional Credits
Worked Example — Three carriers compared for 1 line, iPhone 15 (financed 24 months):
| Carrier | Plan | Device/mo | Taxes/Fees | Autopay | True/mo |
|---|---|---|---|---|---|
| Carrier A | $80 | $35 | $12 | −$5 | $122 |
| Carrier B | $70 | $33 | $10 | −$10 | $103 |
| Carrier C | $65 | $38 | $14 | −$5 | $112 |
24-Month Totals:
- Carrier A: $122 × 24 = $2,928
- Carrier B: $103 × 24 + $35 activation = $2,507
- Carrier C: $112 × 24 − $200 promo = $2,488
Hidden Costs to Check:
- Overage charges (data throttling vs hard cutoff)
- International roaming rates
- Hotspot data caps (often throttled at 15GB even on “unlimited” plans)
- Insurance/protection plan: $12–$18/month adds $288–$432/year
Best Value Rule: Prepaid and MVNO carriers (Mint Mobile, Visible, Cricket) offer the same networks at 40–65% lower cost for single lines — ideal for moderate data users (under 20 GB/month).
How we build and check this calculator
This calculator runs entirely in your browser, so the numbers you enter stay on your device. The math behind it is written by hand and tested against worked examples and standard references before the page goes live.
SuperGlobalCalculator is independently built and maintained. See how we build and verify our calculators.