This is the one calculator on this site without a single right answer. Every extra dollar you have can go toward paying off debt faster or building a safety cushion, and there’s a real tradeoff either way. Enter your numbers below, then drag the slider to see exactly what each split actually does to your timeline.
Why there’s no “optimal” answer here
Putting everything toward debt gets you debt-free faster and costs less in interest, but leaves you without a cushion if something unexpected happens, which can mean going right back into debt to cover it. Putting everything toward savings builds that cushion faster, but means paying more interest for longer on the debt you already have. Neither choice is wrong, it depends on how stable your income is, how much risk you’re comfortable carrying, and what’s already happened to you before.
A common starting point, not a rule
One widely used approach: build a small starter fund first, often around one month of essential expenses, then shift most extra money toward high-interest debt until it’s gone, then rebuild the full emergency fund afterward. This isn’t the only reasonable way to do it, and the right split for you depends on your own situation. Use the slider above to see what different splits actually produce for your numbers, rather than following a rule that doesn’t account for where you stand.
Frequently Asked Questions
How big should my emergency fund actually be?
A common guideline is three to six months of essential expenses, with more stability (a secure job, a second income in the household) supporting a smaller target and more uncertainty (freelance income, being the sole earner) supporting a larger one. This calculator lets you set your own target based on your monthly expenses and however many months feels right for your situation.
Should I stop paying extra on debt entirely until my emergency fund is full?
This is a genuine judgment call rather than a fixed rule, and it depends heavily on your debt’s interest rate. High-interest debt (credit cards in the 20%+ range, for example) is expensive to carry, so many people choose a middle path: a small starter fund first, then aggressive debt payoff, then rebuilding the full fund. Lower-interest debt makes the case for prioritizing savings a bit stronger.
What if I don’t have any extra money to split?
If your minimum payments and essential expenses already use all of your income, this calculator won’t have much to work with, and that’s useful information on its own. In that situation, the more relevant next step is usually looking at ways to reduce expenses or increase income, rather than optimizing a split of money that doesn’t exist yet.