Debt Snowball vs Avalanche Calculator
Compares both orders on the same debts and budget. Each month interest (APR / 12) is added to every debt, all minimums are paid, and the extra payment plus the minimums of debts already paid off go to the target debt.
Example
Debts of $1,000 at 10% ($50 minimum) and $5,000 at 20% ($150 minimum) with $200 extra: debt-free in 18 months; avalanche costs $851.63 of interest, snowball $934.74.