About DebtSnowball
Last reviewed: August 2026
DebtSnowball.co.uk provides free, easy-to-use calculators to help people in the US take control of their debt. There's no sign-up, no paywall, and we never ask for your bank details — every calculation runs entirely in your browser.
Who's behind DebtSnowball
DebtSnowball is written and maintained by Peter Barclay, a UK-based Chartered Mechanical Engineer with a lifelong enthusiasm for solving mathematical problems. It isn't run by a bank, a lender, or a debt-management company — just one engineer who wanted to build clear, honest tools and give them away for free. Peter builds and tests every calculator on the site and personally reviews the guides for accuracy.
Why this site exists
It started with a fascination with the mathematics of debt repayment — specifically the difference between the snowball and avalanche strategies, and the surprising ways a few pounds of extra payment or a different payoff order can change your debt-free date. Building calculators to explore those questions became a way to learn web development, and turning them into free, public educational resources felt like the natural thing to do with them. There's no course to buy and nothing to upsell at the end.
What we offer
- Debt Snowball Calculator — pay off smallest balances first for quick, motivating wins.
- Debt Avalanche Calculator — clear highest-interest debts first to pay the least interest.
- Budget Planner — find the spare cash in your monthly budget.
- Mortgage Refinance Calculator — see whether refinancing saves money after closing costs.
You can browse everything by category — debt calculators, budgeting calculators and mortgage calculators — or start from the debt snowball calculator on our homepage.
How our calculators work
The calculators use standard amortization formulas and fixed repayment (resolving) orders to model how your debts fall over time. Each month we apply interest to every balance, take your minimum payments, then direct any extra payment to a single target debt — the smallest balance for the snowball, the highest interest rate for the avalanche — and roll that freed-up payment onto the next debt as each one clears. Everything runs in your browser on the figures you enter; we never see or store your numbers.
Where a calculation depends on real-world rules or figures — minimum-payment conventions, typical APRs or credit-reporting timelines — we base it on official sources such as the CFPB, the Federal Reserve and nonprofit credit-counseling bodies, and cite them on the relevant guide. We regularly review and test the tools, but we're transparent that mistakes can happen — if you spot one, please tell us via our contact page and we'll correct it.
Our guides
- Debt Snowball Method Guide — how the method works and how to run it by hand.
- Snowball vs Avalanche Guide — motivation against math, and what the difference costs.
- Budgeting Guide for Debt Payoff — build a budget that frees up a sustainable extra payment.
- All debt payoff guides
Independent and self-funded
DebtSnowball.co.uk is an independently-owned site — not part of a bank, a lender or a debt-management company. It's run as a small, self-funded project focused solely on debt payoff, and every calculator is built and tested by Peter Barclay himself. Questions or feedback? See our Contact page.
Not financial advice
We are not financial advisers, and DebtSnowball is not authorised or regulated by the CFPB or any other financial regulator. Our tools and guides are strictly for information and education, based on the figures you enter, and do not constitute financial, legal or debt advice. Debt decisions depend on your personal circumstances, so always treat the results as a starting point rather than a recommendation.
If you're struggling with debt, free help is available from a nonprofit credit counseling agency through the NFCC. For advice tailored to your situation, speak to a licensed financial professional.