DAD MATH
Run the numbers.
Keep the good stuff.
Editable examples. Useful answers. No spreadsheet degree.
All starting numbers are fictional examples, not current prices. Values stay in this page.
Is the extra stop worth it?
Compare the savings on planned purchases with the extra fuel, fees and time.
Cash benefit = basket savings − extra fuel − fees. Time-adjusted benefit also subtracts your optional time value. Vehicle wear is excluded. This compares entered totals; it does not fetch store prices.
The whole family-trip budget
Enter totals for the entire group, including taxes and fees. Keep the emergency buffer separate.
The total includes the buffer. Per-person cost is a simple equal share, not age-based pricing. Print to keep the plan. No reservations are made.
Gas versus electric: energy costs
Compare annual energy spending. This is one part of ownership cost, not a vehicle recommendation.
Use electricity consumption including charging losses and a rate reflecting your home/public charging mix. Purchase price, depreciation, insurance, financing, installation, repairs and taxes are excluded.
What does a shave really cost?
Use your comfortable shaves per refill. Do not keep using a blade just to improve the number.
Annual refill estimate uses 52 weeks. Handle, shaving supplies and partial-pack rounding are excluded. Include shipping and tax in the pack total. No product testing is implied.