Read your runway in ten minutes

Your runway number is hiding in three places: your bank balance, your actual spend history, and a short list of one-off costs you need to pull out before any of it adds up. Most founders either look at ending cash and panic, or look at total cash out and trust a number that includes costs they will never pay again. Ten minutes of clear thinking, with the right framing, fixes both.

Start with cash, but do not stop there

Cash is what your bank says today. Ending cash at month close is your starting point, not your answer. A startup with $610,000 in the bank and a monthly net burn of $82,300 has about 7.4 months of runway. But that is only true if the burn number is representative of the next seven months, and it usually is not on first read.

Net burn is what you actually need

Burn is not total cash out. It is total cash out minus cash actually received. Not revenue you invoiced. Not ARR. Cash in the bank. If you billed $20,000 in consulting last month and $14,000 arrived, your revenue for burn purposes is $14,000. The gap between billed and collected is a real planning risk, and it belongs in the number.

Strip the one-offs before you average

Every early startup has months that are not representative: a legal bill for your incorporation, a year of software billed in January, a security deposit on an office. These are real cash out, but they are not your recurring cost structure. Pull them out before you compute an average. The simplest test is this: would you expect to pay this again next month? If not, it is a one-off.

• Legal fees: incorporations, cap-table restructuring, investor agreements
• Annual software bills that land in a single month
• Security deposits and setup costs for physical space
• A contractor hired for a single project who has since finished

How to build the number

1. Add up the last three months of total cash out.
2. Subtract any obvious one-offs.
3. Divide by three. That is your baseline burn.
4. Subtract your average monthly collections (cash received, not invoiced).
5. Divide ending cash by net burn. That is your runway.

What a healthy number looks like by stage

At pre-seed, 12 months is survivable, 18 is comfortable. At seed, you want at least 15 months post-close to give yourself one full hiring cycle and a meaningful product milestone before you need to raise again. If you are at 9 months or below, that is not a crisis, but it is a clock. At Series A, the conversation shifts toward revenue coverage and growth efficiency, but the underlying arithmetic is the same.

The founders who ran into trouble were not spending recklessly. They were averaging burn across months that were not comparable, and trusting a number built on the wrong inputs.Daniel Reyes

What Vael reads in ten minutes

Connect a bank account or paste a month of transactions and Vael separates the one-offs, computes net burn using cash collected rather than invoiced, and tells you your runway to the week. It also flags anything that made last month unusual, so you know whether the number in front of you is representative of what comes next.