How to Calculate Burn Rate in 60 Seconds

You do not need a CFO or a spreadsheet to calculate burn rate. You need three numbers and one minute. Here is the exact process.

The 60-second process

1. Open your business bank account. Note today's balance.
2. Sum last month's expenses. Total dollars that left the account in the last 30 days.
3. Sum last month's revenue. Total dollars that came IN to the account.
4. Subtract: Expenses − Revenue = Net Burn.
5. Divide: Bank Balance ÷ Net Burn = Runway (months).

That is it. Five steps, one minute, no spreadsheet required.

Worked example

Let us say it is April 6, 2026. You are a seed-stage SaaS founder. Here are your numbers:

Step	Action	Number
1	Bank balance	$340,000
2	March expenses (sum)	$58,000
3	March revenue (sum)	$11,000
4	Net burn = $58K − $11K	$47,000/month
5	Runway = $340K ÷ $47K	7.2 months

You have 7.2 months of runway. That is action-zone territory — time to start raising or tighten spend now, not in two months.

Where the numbers come from

Bank balance

Use your business checking account. If you have multiple accounts (operating account + savings), include both. Exclude personal accounts and credit lines you have not drawn.

Monthly expenses (gross burn)

Include everything that costs you cash:

• Payroll (gross, including employer payroll taxes)
• Contractors and freelancers
• Rent, utilities, internet
• Software subscriptions (sum every recurring SaaS line)
• Marketing and advertising spend
• Legal, accounting, professional services
• Insurance (annual ÷ 12 if paid yearly)
• Bank and payment processing fees
• Travel, meals, conferences
• Equipment and office supplies

Monthly revenue

Use cash actually received, not invoiced. If a customer owes you $20K but has not paid, do not count it. Include:

• Subscription payments collected
• One-time sales
• Service or consulting revenue
• Refund-adjusted net (subtract refunds you issued)

The shortcut for pre-revenue startups

If you have zero revenue, the formula collapses to:

• Net Burn = Monthly Expenses
• Runway = Bank ÷ Monthly Expenses

That is it. Two numbers, one division.

What to do with the answer

Once you have your burn and runway:

• If runway is 18+ months: You are healthy. Focus on growth.
• If runway is 12-18 months: Plan your next raise. Start conversations now.
• If runway is 6-12 months: Actively fundraising or actively cutting. Pick one and commit.
• If runway is under 6 months: Emergency mode. Cut what you can today. Talk to existing investors about a bridge.

Repeat this every month

Burn is not a one-time calculation. It is a monthly ritual. Set a recurring calendar event for the 1st of each month called "Update burn." It takes one minute. Most founders do not do this and pay for it later.

The burn rate calculator handles steps 4 and 5 instantly and shows your zero date and balance trajectory chart. All you do is type three numbers.