What Is a Quit Number and Why It Matters

Your Quit Number is the monthly net income your business needs to generate before you can safely leave your W-2 job. It is not just your salary divided by 12. It accounts for lost benefits, self-employment taxes, and the personal expenses you still need to cover.

Getting this number wrong is one of the most common mistakes side-hustle owners make when going full-time. They replace their paycheck but forget about health insurance, 401k matches, and the extra tax burden that comes with self-employment.

How the Quit Number Works

The calculation starts with three components:

1. Income replacement. The higher of your monthly salary or your actual monthly living expenses. If you spend less than you earn, your expenses are the floor. If you spend more (drawing on savings), your salary is the floor.

2. Benefits overhead. Health insurance on the marketplace, dental, vision, and any employer 401k match you would lose. These costs are invisible while employed, but they hit hard the moment you quit.

3. Self-employment tax grossup. As a W-2 employee, your employer pays half of Social Security and Medicare. As a self-employed person, you pay both halves, currently 15.3% on net earnings. Your business income needs to be high enough to cover this extra tax and still leave you with enough to live on.

The formula: (Income Replacement + Benefits) / (1 - SE Tax Rate) = Quit Number

The Emergency Fund Factor

Reaching your Quit Number does not mean you should quit tomorrow. Revenue fluctuates, especially in the early days of full-time business ownership. The calculator also checks whether your savings cover your target emergency fund, typically 6 months of living expenses plus benefits.

If your business income hits the Quit Number but you have 2 months of savings, you are not ready. One bad month could force you back into job hunting under pressure.

Understanding the Safety Score

The calculator assigns one of three ratings:

Ready – Your business net income meets or exceeds the Quit Number and your emergency fund meets your target. You have a real foundation for the transition.

Almost There – You are within 75% of your Quit Number, or you have hit it but your emergency fund is short. A few more months of consistent growth could close the gap.

Keep Building – Your business income is below 75% of your Quit Number. Focus on growing revenue and building savings before making any moves.

Timeline Projection

If you enter a monthly growth rate, the calculator projects when your business income will cross the Quit Number. This projection uses compound growth, meaning each month builds on the previous month's revenue.

A 5% monthly growth rate sounds modest, but it doubles revenue in about 15 months. A 10% rate doubles in 7 months. Be honest about your actual growth trend. Check your last 3-6 months of revenue to find your real rate.

Scenario Modeling

The calculator lets you test two "what if" levers:

• What if your business grows faster (or slower)? Change the growth rate to see how much the timeline shifts. Even 2-3 percentage points can move your quit date by months.
• What if you cut personal expenses? Reducing your living costs directly lowers your Quit Number. Moving to a cheaper apartment or cutting subscriptions can shave months off your timeline.

Common Mistakes When Planning to Quit

1. Forgetting about quarterly tax payments. Self-employed people pay estimated taxes four times a year. Budget for these from day one.
2. Counting gross business revenue instead of net income. Your Quit Number is about what you take home after business expenses.
3. Not accounting for income volatility. A W-2 salary is predictable. Business revenue is not. Build a buffer into your plan.
4. Quitting the moment income matches. One good month does not make a trend. Wait for 3+ consecutive months above your Quit Number before making the leap.
5. Ignoring retirement contributions. If you were getting a 401k match, you need to replace that savings rate on your own.

When to Use This Calculator

Run this calculator when you are seriously considering full-time self-employment. It is most useful when your side business is already generating revenue and you have a reasonable growth trend to project from.

Pair it with the Burn Rate Calculator to understand how long your savings last if revenue dips, and the Cash Flow Forecast to model your first 12 months after quitting. The Quarterly Tax Estimator helps you plan for those estimated payments you will owe.