Before you quit your job to start a company, you need to know exactly how long you can survive on your savings. Personal runway is the number of months your liquid savings will support you based on your spending. It's the most important number for aspiring entrepreneurs to understand because it tells you whether you have the financial cushion to take the leap safely.
Runway isn't just about having savings. It's about understanding the gap between your current lifestyle and your bare-minimum survival spending, and knowing whether your emergency fund buys you 6 months, 12 months, or 18+ months of safety. This calculator shows you both scenarios and helps you identify your monthly flex for cutting expenses in tough times.
How to Read Your Results
The calculator shows you two runway numbers: one at your current spending level and one if you cut back to survival mode. The current lifestyle runway tells you how long you can operate without cutting anything. The survival mode runway shows your true financial safety net if expenses become critical.
The most important output is your monthly flex, the gap between current and survival spending. If you have 1,500 in monthly flex, you have significant room to cut expenses if your startup revenue comes in slower than expected. If your flex is under 500, you're operating with minimal margin and should plan conservatively.
Runway Benchmarks for Entrepreneurs
- 18+ months: You're in a strong position. You have time to build your business without revenue pressure. Your personal finances won't be the bottleneck.
- 12-17 months: Good runway. You can operate comfortably but should have concrete plans for revenue within a year.
- 6-11 months: Acceptable but tight. You need to be aggressive about reaching customers and generating early revenue.
- Under 6 months: High risk. Only consider taking the leap if you have other income sources (partner's salary, side consulting work) or are willing to return to work quickly if needed.
Common Mistakes
Mistake 1: Counting retirement accounts as runway
Your 401k or IRA is not emergency money. Early withdrawals carry tax penalties and defeat the purpose of retirement savings. Only count liquid savings you can access without penalties or taxes. This means checking, savings, brokerage, and possibly home equity, but not retirement accounts.
Mistake 2: Overestimating survival spending
Many people estimate their bare minimum too high. True survival includes rent or mortgage, utilities, basic groceries, and essential insurance. It does not include dining out, entertainment, subscriptions, or vacation. Be honest about what you could cut immediately if you had to.
Mistake 3: Using average income instead of guaranteed income
If you're planning to earn money while building your startup, only count income you're confident you can maintain consistently. Sporadic consulting gigs or hoped-for revenue don't count. Conservative estimates here are better than optimistic ones.
Mistake 4: Forgetting about taxes and bigger expenses
Your runway calculation uses take-home spending, but if you're self-employed, you need to factor in quarterly tax payments and annual expenses like insurance renewals. Build an extra 2-3 month buffer into your runway target to account for lumpy expenses.
Frequently Asked Questions
What counts as liquid savings?
Liquid savings are money you can access within days without penalties. This includes checking accounts, savings accounts, and brokerage accounts. Home equity and retirement accounts do not count because withdrawing from them triggers taxes and penalties. High-yield savings accounts count even though they take 1-2 business days to transfer.
Can I include stock I own in my runway calculation?
Only if the stock is in a regular brokerage account, not a 401k or IRA. If you own individual stocks or index funds in a taxable account, yes, include them. However, be conservative because you'll owe capital gains taxes when you sell. If a stock is worth 10,000 but you'll owe 2,000 in taxes, count 8,000 as usable savings.
Should I factor in my partner's income when calculating runway?
Only count your own liquid savings for your personal runway, but do separate calculations for household runway if your partner can support some of your expenses. Your personal runway shows your individual safety net, while household runway shows your true financial position if you can pool resources. These are two different questions, and the answer matters for how much risk you can take.
What if my expenses are seasonal or lumpy?
Calculate an average monthly spend across a full year, not just the cheapest month. If you spend 3,000 most months but 5,000 in three months (taxes, insurance, car repair), your true average is closer to 3,500. Use this average in the runway calculation, not the minimum. This gives you a more realistic picture of your actual burn rate.
How much runway is enough for my specific situation?
That depends on your business model and financial obligations. If you have dependents, zero other income sources, or a high monthly burn rate, target 18-24 months. If you're single with low expenses and confident in your sales ability, 12 months might be enough. Use this calculator with the Leap Scorecard to assess your overall readiness, not just runway alone.