Burn Rate Calculator

Calculate monthly burn rate and runway to measure cash consumption and sustainability

About the Burn Rate Calculator

The Burn Rate Calculator is a vital financial health tool designed for startup founders, small business owners, and corporate finance officers to track capital consumption. In the early stages of a venture, companies often spend more than they earn as they invest in product development, marketing, and scaling operations. This calculator quantifies that spending gap, providing a clear view of how much cash is exiting the business each month. By inputting your starting and ending cash balances over a specific duration, you can distinguish between gross burn (total spending) and net burn (actual losses after revenue).

Understanding these metrics is the difference between strategic growth and sudden insolvency. Investors use burn rate as a primary indicator of operational efficiency and management discipline. If a company is burning cash too quickly without reaching key milestones, it may fail to secure subsequent funding rounds. This tool eliminates guesswork, allowing leadership to make data-driven decisions about hiring, expansion, or the need for immediate cost-cutting measures to extend the company's lifespan.

Formula

Monthly Burn Rate = (Starting Cash - Ending Cash) / Number of Months

The Monthly Burn Rate formula measures the rate at which a company consumes its cash reserves. Starting Cash represents the balance at the beginning of a specific period, while Ending Cash is the balance remaining at the end of that period. By dividing the difference by the number of months in that timeframe, you determine the average monthly cash outflow.

To find the runway, use the formula: Runway = Total Cash / Monthly Burn Rate. This tells you exactly how many months the business can survive if spending and revenue remain constant. In these calculations, cash should include all liquid assets available for immediate use.

Worked examples

Example 1: A mobile app startup has $170,000 in the bank. Last month they started with $190,000 and ended with $170,000.

Starting Cash: $190,000
Ending Cash: $170,000
Burn Rate = ($190,000 - $170,000) / 1 month = $20,000
Runway = $170,000 / $20,000 = 8.5 months

Result: $20,000 per month burn rate with 8.5 months of runway. At this pace, the company will run out of cash in mid-September.

Example 2: A SaaS company tracks their cash over a quarter. On January 1st they had $635,000 and on March 31st they had $500,000.

Starting Cash: $635,000
Ending Cash: $500,000
Total Difference: $135,000
Months: 3
Monthly Burn Rate = $135,000 / 3 = $45,000
Runway = $500,000 / $45,000 = 11.11 months

Result: $45,000 per month average burn rate with 11.1 months of runway. The company has nearly a year to reach profitability or raise more funds.

Common use cases

A tech startup needs to determine if their current seed funding will last until the scheduled Series A round.
An e-commerce business wants to see how much they can afford to spend on customer acquisition while remaining solvent for 12 months.
A non-profit organization tracks monthly administrative spending against their annual grant disbursement.
A founder evaluates whether they need to implement a hiring freeze to avoid running out of cash by year-end.

Pitfalls and limitations

Ignoring seasonal fluctuations that can temporarily spike or dip burn rates.
Failing to account for one-time capital expenditures like equipment purchases that don't reflect recurring monthly burn.
Miscalculating runway by including 'promised' investment or revenue that is not yet liquid cash.
Using gross burn instead of net burn when the company is generating some revenue, which underestimates the runway.

Frequently asked questions

what is the difference between gross burn and net burn rate?

Gross burn is the total amount of cash spent on operating expenses each month, regardless of revenue. Net burn is the actual amount of money the company loses, calculated by subtracting monthly revenue from gross burn. Net burn is the more critical metric for determining runway.

how many months should I use for average burn rate?

Burn rate is typically calculated on a monthly basis. However, because spending and revenue can fluctuate, it is best practice to look at a 3-month or 6-month average to get a more accurate picture of your financial trajectory.

is a high burn rate always bad for a startup?

No, investors generally view a high burn rate as a major risk unless it is tied to aggressive, efficient growth in a 'winner-take-all' market. High burn without corresponding revenue growth often leads to a 'down round' or bankruptcy.

how do I calculate my company runway?

Cash runway is the amount of time expressed in months that a company can continue to operate before running out of money. It is calculated by dividing your current cash balance by your monthly net burn rate.

what are the best ways to reduce burn rate?

To reduce burn rate, companies usually focus on cutting non-essential operating expenses (SaaS subscriptions, travel, office perks), freezing hiring, or pivoting to increase high-margin revenue streams quickly.