Pro workbook: Debts, Schedule, Summary, Setup, Formulas. Sample data, real formulas.
| Debt payoff | ||||||
| List the debts. Pick snowball (smallest balance first) or avalanche (highest rate first); the order and the numbers follow. | ||||||
| Extra per month | 300.00 | on top of every minimum | ||||
| Method | Snowball | Snowball: smallest balance first · Avalanche: highest rate first | ||||
| First payment | Oct 2026 | |||||
| Debt | Balance | APR | Minimum | Order | Interest / mo | Months at min |
| Visa | 4,200.00 | 21.9% | 120.00 | 3 | 76.65 | 57 |
| Car loan | 9,800.00 | 6.9% | 310.00 | 4 | 56.35 | 35 |
| Store card | 850.00 | 26.9% | 40.00 | 1 | 19.05 | 30 |
| Student loan | 14,500.00 | 4.5% | 160.00 | 5 | 54.38 | 111 |
| Personal loan | 3,100.00 | 12.9% | 95.00 | 2 | 33.33 | 41 |
| Total | 32,450.00 | 8.9% | 725.00 | 239.75 | ||
| Paying per month | 1,025.00 | minimums + extra | ||||
| Order 1 is the debt all the extra money goes to first (yellow). When it's paid off, its minimum joins the extra and rolls to order 2 — that's the snowball. | ||||||
| Months at min: how long each debt takes on its minimum alone, no extra. Red: the minimum doesn't cover the interest, so it never ends. | ||||||
| Weighted APR is balance-weighted. Interest / mo is what the debts cost this month before any principal. |
| Schedule | |||||||||||||||||||||||||||
| Month by month, debts in payoff order. Each pays its minimum; the extra — and every minimum freed by a paid-off debt — goes to the first debt still open. | |||||||||||||||||||||||||||
| Extra | 300.00 | min · rate → | 40.00 | 26.9% | 95.00 | 12.9% | 120.00 | 21.9% | 310.00 | 6.9% | 160.00 | 4.5% | |||||||||||||||
| start → | 850.00 | Personal loan | 3,100.00 | Visa | 4,200.00 | Car loan | 9,800.00 | Student loan | 14,500.00 | ||||||||||||||||||
| # | Month | Paid | Balance | Pool → | Paid | Balance | Pool → | Paid | Balance | Pool → | Paid | Balance | Pool → | Paid | Balance | Pool → | Paid | Balance | Pool → | Paid | Balance | Pool → | Paid | Balance | Pool → | Paid total | Owed total |
| 1 | Oct 2026 | 340.00 | 529.05 | 95.00 | 3,038.33 | 120.00 | 4,156.65 | 310.00 | 9,546.35 | 160.00 | 14,394.38 | 1,025.00 | 31,664.76 | ||||||||||||||
| 2 | Nov 2026 | 340.00 | 200.91 | 95.00 | 2,975.99 | 120.00 | 4,112.51 | 310.00 | 9,291.24 | 160.00 | 14,288.36 | 1,025.00 | 30,869.01 | ||||||||||||||
| 3 | Dec 2026 | 205.41 | 134.59 | 229.59 | 2,778.39 | 120.00 | 4,067.56 | 310.00 | 9,034.66 | 160.00 | 14,181.94 | 1,025.00 | 30,062.55 | ||||||||||||||
| 4 | Jan 2027 | 340.00 | 435.00 | 2,373.26 | 120.00 | 4,021.79 | 310.00 | 8,776.61 | 160.00 | 14,075.12 | 1,025.00 | 29,246.78 | |||||||||||||||
| 5 | Feb 2027 | 340.00 | 435.00 | 1,963.77 | 120.00 | 3,975.19 | 310.00 | 8,517.08 | 160.00 | 13,967.90 | 1,025.00 | 28,423.94 | |||||||||||||||
| 6 | Mar 2027 | 340.00 | 435.00 | 1,549.88 | 120.00 | 3,927.74 | 310.00 | 8,256.05 | 160.00 | 13,860.28 | 1,025.00 | 27,593.95 | |||||||||||||||
| 7 | Apr 2027 | 340.00 | 435.00 | 1,131.54 | 120.00 | 3,879.42 | 310.00 | 7,993.52 | 160.00 | 13,752.26 | 1,025.00 | 26,756.74 | |||||||||||||||
| 8 | May 2027 | 340.00 | 435.00 | 708.70 | 120.00 | 3,830.22 | 310.00 | 7,729.48 | 160.00 | 13,643.83 | 1,025.00 | 25,912.23 | |||||||||||||||
| 9 | Jun 2027 | 340.00 | 435.00 | 281.32 | 120.00 | 3,780.12 | 310.00 | 7,463.92 | 160.00 | 13,534.99 | 1,025.00 | 25,060.35 | |||||||||||||||
| 10 | Jul 2027 | 340.00 | 284.34 | 150.66 | 270.66 | 3,578.45 | 310.00 | 7,196.84 | 160.00 | 13,425.75 | 1,025.00 | 24,201.04 | |||||||||||||||
| 11 | Aug 2027 | 340.00 | 435.00 | 555.00 | 3,088.76 | 310.00 | 6,928.22 | 160.00 | 13,316.10 | 1,025.00 | 23,333.08 | ||||||||||||||||
| 12 | Sep 2027 | 340.00 | 435.00 | 555.00 | 2,590.13 | 310.00 | 6,658.06 | 160.00 | 13,206.04 | 1,025.00 | 22,454.23 | ||||||||||||||||
| 13 | Oct 2027 | 340.00 | 435.00 | 555.00 | 2,082.40 | 310.00 | 6,386.34 | 160.00 | 13,095.56 | 1,025.00 | 21,564.30 | ||||||||||||||||
| 14 | Nov 2027 | 340.00 | 435.00 | 555.00 | 1,565.40 | 310.00 | 6,113.06 | 160.00 | 12,984.67 | 1,025.00 | 20,663.13 | ||||||||||||||||
| 15 | Dec 2027 | 340.00 | 435.00 | 555.00 | 1,038.97 | 310.00 | 5,838.21 | 160.00 | 12,873.36 | 1,025.00 | 19,750.54 | ||||||||||||||||
| 16 | Jan 2028 | 340.00 | 435.00 | 555.00 | 502.93 | 310.00 | 5,561.78 | 160.00 | 12,761.64 | 1,025.00 | 18,826.35 | ||||||||||||||||
| 17 | Feb 2028 | 340.00 | 435.00 | 512.11 | 42.89 | 352.89 | 5,240.87 | 160.00 | 12,649.50 | 1,025.00 | 17,890.37 | ||||||||||||||||
| 18 | Mar 2028 | 340.00 | 435.00 | 555.00 | 865.00 | 4,406.01 | 160.00 | 12,536.94 | 1,025.00 | 16,942.95 | |||||||||||||||||
| 19 | Apr 2028 | 340.00 | 435.00 | 555.00 | 865.00 | 3,566.34 | 160.00 | 12,423.95 | 1,025.00 | 15,990.29 | |||||||||||||||||
| 20 | May 2028 | 340.00 | 435.00 | 555.00 | 865.00 | 2,721.85 | 160.00 | 12,310.54 | 1,025.00 | 15,032.39 | |||||||||||||||||
| 21 | Jun 2028 | 340.00 | 435.00 | 555.00 | 865.00 | 1,872.50 | 160.00 | 12,196.70 | 1,025.00 | 14,069.20 | |||||||||||||||||
| 22 | Jul 2028 | 340.00 | 435.00 | 555.00 | 865.00 | 1,018.27 | 160.00 | 12,082.44 | 1,025.00 | 13,100.71 | |||||||||||||||||
| 23 | Aug 2028 | 340.00 | 435.00 | 555.00 | 865.00 | 159.13 | 160.00 | 11,967.75 | 1,025.00 | 12,126.88 | |||||||||||||||||
| 24 | Sep 2028 | 340.00 | 435.00 | 555.00 | 160.04 | 704.96 | 864.96 | 11,147.67 | 1,025.00 | 11,147.67 | |||||||||||||||||
| 25 | Oct 2028 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 10,164.47 | 1,025.00 | 10,164.47 | ||||||||||||||||||
| 26 | Nov 2028 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 9,177.59 | 1,025.00 | 9,177.59 | ||||||||||||||||||
| 27 | Dec 2028 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 8,187.01 | 1,025.00 | 8,187.01 | ||||||||||||||||||
| 28 | Jan 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 7,192.71 | 1,025.00 | 7,192.71 | ||||||||||||||||||
| 29 | Feb 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 6,194.68 | 1,025.00 | 6,194.68 | ||||||||||||||||||
| 30 | Mar 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 5,192.91 | 1,025.00 | 5,192.91 | ||||||||||||||||||
| 31 | Apr 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 4,187.38 | 1,025.00 | 4,187.38 | ||||||||||||||||||
| 32 | May 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 3,178.08 | 1,025.00 | 3,178.08 | ||||||||||||||||||
| 33 | Jun 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 2,165.00 | 1,025.00 | 2,165.00 | ||||||||||||||||||
| 34 | Jul 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 1,148.12 | 1,025.00 | 1,148.12 | ||||||||||||||||||
| 35 | Aug 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 127.43 | 1,025.00 | 127.43 | ||||||||||||||||||
| 36 | Sep 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 127.91 | 897.09 | 897.09 | 897.09 | 897.09 | 127.91 | ||||||||||||||||
| 37 | Oct 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 1,025.00 | 1,025.00 | 1,025.00 | ||||||||||||||||||
| 38 | Nov 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 1,025.00 | 1,025.00 | 1,025.00 | ||||||||||||||||||
| 39 | Dec 2029 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 1,025.00 | 1,025.00 | 1,025.00 | ||||||||||||||||||
| 40 | Jan 2030 | 340.00 | 435.00 | 555.00 | 865.00 | 1,025.00 | 1,025.00 | 1,025.00 | 1,025.00 |
| Summary | ||||||
| When each debt ends, what it cost, and what the extra money buys you. | ||||||
| Order | Debt | Balance | Paid off | Months | Interest paid | At minimums |
| 1 | 850 | 850.00 | Dec 2026 | 3 | 35.41 | 30 |
| 2 | 3100 | 3,100.00 | Jul 2027 | 10 | 213.93 | 41 |
| 3 | 4200 | 4,200.00 | Feb 2028 | 17 | 992.77 | 57 |
| 4 | 9800 | 9,800.00 | Sep 2028 | 24 | 862.93 | 35 |
| 5 | 14500 | 14,500.00 | Sep 2029 | 36 | 1,447.87 | 111 |
| 0 | ||||||
| 0 | ||||||
| 0 | ||||||
| All debts | 32,450.00 | Sep 2029 | 36 | 3,552.91 | ||
| Debt-free in | 36 | months | ||||
| Debt-free by | Sep 2029 | |||||
| Total interest | 3,552.91 | with the extra and the snowball | ||||
| Paying per month | 1,025.00 | minimums + extra | ||||
| Total paid | 36,002.91 | balances + interest | ||||
| 'At minimums' is each debt on its own minimum with no extra — the closed-form months from the Debts sheet. Compare it with 'Months' to see what the extra buys. | ||||||
| A debt still open after 120 months shows 0 in Months and turns red: raise the extra or the minimum. |
| Setup | |
| The extra money per month, the method, and the first payment month. | |
| Extra per month | 300.00 |
| Method | Snowball |
| First payment (1st of month) | 2026-10-01 |
| Snowball pays the smallest balance first — quick wins. Avalanche pays the highest rate first — least interest. Switch and compare the Summary; the Schedule recalculates. |
| How the formulas work | ||
| Every formula in this workbook, in plain words. Nothing is hidden and nothing needs a macro. Formulas are shown without the leading = sign. | ||
| Where | Formula | What it does |
| Debts · Order (snowball) | COUNTIF($B$8:$B$15,"<"&B8)+COUNTIF($B$8:B8,B8) | How many debts have a smaller balance, plus how many equal-or-this ones sit at or above this row — a rank without RANK, ties broken by position. Avalanche does the same with rates and ">". |
| Debts · Months at min | ROUNDUP(-LN(1-B8*C8/12/D8)/LN(1+C8/12),0) | The closed form of an amortizing loan: n = −ln(1 − rB/P) / ln(1 + r) with r the monthly rate. If P ≤ rB the log is undefined — the payment doesn't cover interest — so the cell shows 0 and turns red. |
| Schedule · debt for column k | INDEX(Debts!$A$8:$A$15,MATCH(1,Debts!$E$8:$E$15,0)) | Columns are in payoff order, not input order: each block looks up the debt whose Order is k. Its minimum, rate and starting balance sit in rows 3–4 above the block. |
| Schedule · Paid | IF(prev<=0,0,MIN(prev+ROUND(prev*rate/12,2), min+pool_in)) | A closed debt pays nothing. Otherwise: the minimum plus whatever arrived from the previous block, capped at balance plus this month's interest. |
| Schedule · Balance | IF(prev<=0,0,ROUND(prev+interest-paid,2)) | Previous balance plus interest minus the payment, to the cent. |
| Schedule · Pool → | pool_in+min-paid | What flows to the next block: the money that arrived, plus this debt's minimum, minus what it actually paid. A closed debt passes its whole minimum on — that's the snowball rolling. |
| Schedule · first block's pool_in | $B$3 | The extra per month from Setup. Every other block reads the Pool → cell to its left. |
| Summary · Months | MATCH(0,Schedule!D6:D125,0) | The first month whose balance is zero. IFERROR → 0 when the debt is still open after 120 months. |
| Summary · Interest paid | SUM(Schedule!C6:C125)-Schedule!D4 | Everything paid minus the starting balance. |
| Summary · Debt-free by | EDATE(Setup!$B$5,E13-1) | First payment month plus the last month's number. |