When I wrote about snowball versus avalanche, the sheet I shared did one job: you picked a method, and it told you the order and the date. Useful. But it left the real question hanging.
The real question isn't "which order." It's "if I find another $100 a month, how much sooner am I done?"
That's the number that gets you to sell the bike, cancel the thing, take the extra shift. So I rebuilt the sheet around it.
What it does now
You still enter up to eight debts: name, balance, rate, minimum payment. Then three things changed.
1. Four ways to prioritize, from a dropdown.
- Snowball. Smallest balance first. Quickest wins.
- Avalanche. Highest interest rate first. Least interest paid.
- Largest balance first. Some people want the big one gone. Now you can see what that costs.
- Highest payment first. Kill the debt with the biggest minimum, free up the most monthly cash fastest.
Switch between them and the order, the payoff months, the debt-free date, and the total interest all update.
2. A compare table.
Under the results there are three rows: minimums only, your plan, and your plan with whatever extra amount you type in. Each row shows the debt-free month and total interest, and a sentence that does the subtraction for you. "Debt-free 14 months sooner than minimums only, and $1,754 less interest." That's the sentence I wanted.
3. A month-by-month schedule.
A second tab shows every month for fifteen years: each balance in pay order, the total, and what you paid. You can literally watch the small ones hit zero and the payment roll onto the next.
What the sample numbers say
The sheet ships with example debts, not mine. Five of them, about $17,400 total, with minimums of $580 a month and an extra $300 on top. Here's what the four methods do with the same money:
| Method | Debt-free | Total interest |
|---|---|---|
| Snowball | 22 months | $1,646 |
| Avalanche | 22 months | $1,496 |
| Largest balance first | 23 months | $2,285 |
| Highest payment first | 23 months | $2,285 |
Two things jump out. Snowball and avalanche finish the same month; the difference is $150 of interest over almost two years. And attacking the biggest loan first costs $640 more and finishes later. It feels productive. It isn't.
Now the compare table, using snowball:
| Debt-free | Total interest | |
|---|---|---|
| Minimums only | 36 months | $3,400 |
| Minimums + $300 extra | 22 months | $1,646 |
| Add $100 more | 20 months | $1,438 |
The first $300 buys you fourteen months. The next $100 buys you two more, and another $208. That's the shape of it: the first extra dollars matter enormously, and every dollar after still matters. Put your own numbers in and the shape will be different, but the lesson holds.
How the math works
Every month, the sheet charges each debt its interest, pays every minimum, and sends everything left in your fixed monthly budget to the first debt in the order. When that debt dies partway through a month, the leftover goes straight to the next one the same month, and its minimum stays in the budget forever. Freed-up payments never leak back into your spending. That's the whole trick, and the sheet does it for you.
Interest is estimated monthly from the APR. Your statements will differ a little. The dates won't be off by much.
Get it
It's free on the resources page, no sign-up, no email. Download it and open it in Excel, Numbers, or Google Sheets. Fill in the shaded cells, pick a method, and read the compare table. Then go find another $50 and read it again.
Pair it with the five-minute budget. That sheet tells you what's left over each month. This one tells you what that number is worth.
