How to Calculate Runway for a Startup in Google Sheets
Build a startup runway calculator in Google Sheets. Track gross burn, net burn, and months of cash with formulas that update automatically.
How to calculate runway for a startup comes down to one formula: cash on hand divided by monthly net burn. But a single number in a cell won't tell you when you need to start fundraising, how a new hire changes your timeline, or whether your revenue growth is actually extending your life. This guide walks you through building a runway model in Google Sheets that answers all of that — from organizing your burn data to stress-testing scenarios before your next board meeting.
What You'll Need
- A Google Sheets account with edit access to your financial workbook
- Your current bank balance (or latest bank statement)
- A rough monthly expense breakdown (payroll, software, office, etc.)
- Monthly revenue figures for the past 3-6 months (even if $0)
- Approximately 30 minutes
Step-by-Step Guide
Set Up Your Cash and Expense Inputs
Before any formula touches a cell, you need a clean inputs section. Put everything you might change in one place — this makes scenario modeling in Step 6 much faster.
Create a tab called Inputs with the following rows:
| Row | Label | Example Value |
|---|---|---|
| B2 | Cash on hand | $480,000 |
| B3 | Payroll (monthly) | $42,000 |
| B4 | Software & tools | $3,800 |
| B5 | Office & facilities | $2,200 |
| B6 | Marketing | $4,500 |
| B7 | Other OpEx | $2,500 |
| B8 | Monthly revenue | $8,000 |
- Keep cash on hand as a single number you update once per month after reconciling accounts
- Break payroll out separately — it's almost always the largest lever in a burn scenario
- Include a catch-all "Other OpEx" row so you don't obsess over perfect categorization early on
Pro Tip
Pull your expense figures from your accounting software (QuickBooks, Xero, Mercury) by exporting last month's P&L. Don't estimate from memory — payroll taxes and benefits regularly add 20-30% on top of base salaries.Calculate Gross Burn and Net Burn
Gross burn is total cash out per month. Net burn subtracts any revenue coming in. The distinction matters because investors and founders use both terms — and conflating them in a pitch is a fast way to lose credibility.
On your Inputs tab (or a new Runway tab), add:
Gross Burn = SUM(B3:B7)
With the example values above, gross burn is $55,000/month.
Net Burn = Gross Burn - B8
Net burn = $55,000 − $8,000 = $47,000/month.
- Gross burn tells you how fast you spend; net burn tells you how fast you're actually consuming cash
- Early-stage startups with no revenue have identical gross and net burn
- If net burn is negative, you're cash-flow positive — the runway calculation still applies but in reverse (you're accumulating cash)
- According to the Startup Genome Report 2023, the median pre-seed startup burns between $15,000 and $50,000 per month depending on team size
Pro Tip
Named ranges make formulas readable. In Google Sheets, go to Data → Named ranges and name B2cash_on_hand, the gross burn cell gross_burn, etc. Your runway formula becomes =cash_on_hand/net_burn instead of =B2/B12.Calculate How to Determine Runway for a Startup
Runway in months = cash on hand ÷ net burn rate. This is the core formula this entire guide builds toward.
Runway (months) = cash_on_hand / net_burn
With $480,000 cash and $47,000 net burn:
= 480000 / 47000
= 10.2 months
- Round to one decimal place — false precision beyond that isn't useful
- Add a companion cell that converts months to a calendar date:
=EDATE(TODAY(), ROUND(runway_months, 0)) - That date formula gives you the estimated zero-cash date, which is more viscerally useful than "10.2 months"
- As of April 2026, with Series A timelines running 6-9 months from first meeting to close (per Carta's State of Private Markets Q4 2025 report), a 10-month runway means you're already in fundraising territory
Pro Tip
Color-code the runway cell with conditional formatting: red below 6 months, yellow 6-12, green above 12. One glance tells you where you stand.Build a 12-Month Cash Projection
A static runway number is a snapshot. A monthly projection shows you the shape of your burn — whether you're burning flat, accelerating, or decelerating as revenue grows.
Create a Projection tab with columns for each month:
| Column | A | B | C | D |
|---|---|---|---|---|
| Row 1 | Month | Starting Cash | Net Burn | Ending Cash |
| Row 2 | Apr 2026 | =cash_on_hand | =net_burn | =B2-C2 |
| Row 3 | May 2026 | =D2 | =net_burn | =B3-C3 |
- Drag rows 3 through 13 down to complete 12 months
- Ending cash in each month becomes starting cash in the next — this chains your model correctly
- Add a fifth column for cumulative revenue if you're projecting growth:
=B8*(1+monthly_growth_rate)^(ROW()-2) - Your runway end date is the first month where ending cash drops below zero
Pro Tip
Add a sparkline above the ending cash column to visualize the cash curve at a glance:=SPARKLINE(D2:D13, {"charttype","line";"color","#E53935"}).Add a Hiring and Expense Sensitivity Table
Every startup founder eventually asks: "what happens to runway if we hire two engineers?" Build the answer before you're asked.
Create a sensitivity table on the Projection tab:
New monthly cost of hire = salary / 12 * 1.25
(the 1.25 accounts for payroll taxes and benefits — typically 20-25% of base per SHRM's 2024 Employee Benefits Survey)
Then create a table with new hire count (0–4) across columns and revenue growth rate (0%, 5%, 10%, 15%) down rows. Each cell runs the runway formula with modified inputs:
=($B$2) / (gross_burn + (hire_count * avg_monthly_hire_cost) - (B8 * (1 + growth_rate)^6))
- The
^6projects revenue 6 months out, assuming hires take time to drive growth - This table immediately surfaces the trade-off: hiring 2 engineers at $140K each cuts ~3 months of runway unless revenue grows at 8%+
- Share this table with your co-founder or board rather than giving them a single number
Model Raise and Revenue Scenarios
How to calculate runway for a startup changes the moment you add capital or hit a revenue milestone. Build a scenarios block that lets you toggle assumptions without breaking your main model.
Add a Scenarios tab with 3 preset columns:
| Scenario | Cash Added | Monthly Burn Change | New Runway |
|---|---|---|---|
| Base | $0 | $0 | =base_runway |
| Raise $1M Seed | $1,000,000 | $0 | =(cash_on_hand+1000000)/net_burn |
| Cut 2 engineers | $0 | -$23,333 | =cash_on_hand/(net_burn-23333) |
| Hit $30K MRR | $0 | -$22,000 net | =cash_on_hand/(net_burn-22000) |
- The "$1M seed + same burn" scenario typically extends runway by 21 months at a $47K/month burn rate
- The cut scenario shows that layoffs are a runway extension tool — painful but quantifiable
- Y Combinator's standard advice is to target 18-24 months of runway after a seed round, giving enough time to reach a Series A milestone without distraction
Pro Tip
Use a dropdown in cell A1 of your Projection tab linked to scenario names, then useIF or CHOOSE to swap the burn and cash inputs automatically. Your whole projection updates with one cell change.Set Up Automatic Monthly Updates
A runway model you update manually every quarter is a model that will be wrong when you need it most. Wire up a simple refresh workflow so your numbers stay current.
If you're using ModelMonkey inside Google Sheets, you can ask it to pull your latest bank balance and expense totals from a connected data source and update the Inputs tab automatically — no Apps Script required. For a manual workflow:
- Export your accounting software's monthly P&L as CSV
- Paste it into a Raw Data tab in your workbook
- Use
SUMIFon the expense categories to populate your Inputs tab automatically: - Update cash on hand from your bank statement on the 1st of each month
- Keep a version history by duplicating the Inputs tab each month before updating (rename it "Inputs_Mar2026", etc.)
Pro Tip
Add a "Last updated" cell at the top of Inputs with=TODAY() so anyone opening the model can immediately see whether the data is current.Wrapping Up
You've built a startup runway calculator that goes from raw expense data to scenario-tested projections. The core formula — cash divided by net burn — takes 30 seconds to write, but the model around it is what makes it useful for decisions: when to fundraise, whether to hire, how much revenue growth actually moves the needle.
The friction isn't the math. It's keeping the inputs current. Most founders update their runway model right before a board meeting, which means they're discovering problems at the same time they're explaining them. Update it monthly, automate what you can, and you'll never be surprised by your own zero-cash date.
Try ModelMonkey free for 14 days — it works in both Google Sheets and Excel.
Frequently Asked Questions
What's the difference between gross burn and net burn?
Gross burn is total cash spent per month — payroll, rent, software, everything. Net burn subtracts revenue: if you spend $55,000 and collect $8,000, your net burn is $47,000. Investors typically ask about net burn when evaluating runway, because it reflects how fast you're actually consuming cash, not just how much you're spending.
How often should I update my startup runway calculation?
Monthly is the minimum for most early-stage startups. If your monthly burn exceeds $100,000, update it weekly — at that rate, a single miscalculation costs you days of runway. Always update immediately after a significant event: a new hire, a customer churning, or a fundraise closing.
What's a healthy runway for a startup in 2026?
18-24 months is the widely cited target after a seed or Series A close, per Y Combinator's standard guidance. Carta's State of Private Markets Q4 2025 report shows median time from first investor meeting to Series A close running approximately 6-9 months, which means anything below 12 months of runway puts you in active fundraising mode whether you're ready or not.
Does runway change if I'm growing revenue?
Yes — and this is where the static formula breaks down. If your net burn is $47,000 today but revenue is growing 10% month-over-month, your effective burn rate shrinks each month. The 12-month projection model in Step 4 handles this correctly by recalculating net burn each row as revenue compounds. A static `cash / burn` calculation will understate your actual runway once you have meaningful revenue growth.
Should I include accounts receivable in my cash on hand?
Only if the receivables are collected within 30 days and historically reliable. Runway calculations are meant to be conservative — using expected cash rather than cash in the bank introduces optimism bias at exactly the moment you need clarity. Keep a separate "best case" scenario that adds expected AR, but base your primary runway number on actual bank balance only.