The debt snowball and avalanche both run on one number: your monthly surplus. That's the money left over after every essential is paid. This planner works it out for you by converting every income source and expense — however often it's paid — into a single monthly figure, then subtracting outgoings from income.
Once you can see that number clearly, two things happen. First, you know exactly how much extra you can commit to your debt payoff plan. Second, the category breakdown shows where your money actually goes, so you can find more surplus by trimming the categories that have quietly crept up.
Little costs add up
The planner flags smaller recurring payments (under £50 a month) separately, because these are the costs people most often overlook. A daily coffee, a handful of streaming subscriptions, and a couple of takeaways can easily total £150–£200 a month — enough, redirected, to shave years off a credit-card balance.
Frequently Asked Questions
Add every income source and expense, choosing a category and how often it's paid. The planner converts everything to a monthly figure, then shows total income, expenses, net balance, a category breakdown, and charts. The net balance is the spare cash you could put toward debt or savings.
Weekly costs are multiplied by 52.18 then divided by 12 (about 4.35 weeks per month). Bi-weekly uses 26.09 payments a year. Quarterly is divided by 3, annual by 12 — giving an accurate average monthly figure.
A popular starting point is 50/30/20: 50% of take-home pay on needs, 30% on wants, 20% on savings and debt. If you're clearing debt, many people prioritise debt payments. The key idea is that every pound has a job.
Budgeting reveals your net monthly surplus — the money left after essentials. That surplus powers the debt snowball or avalanche. Even finding an extra £100–£200 a month by trimming small recurring costs can cut years off a repayment plan.
Disclaimer: This tool is for informational purposes only and does not constitute financial advice. Figures are estimates based on the information you enter. For personal advice, consult an FCA-regulated adviser.