Cash runway calculator for small business
Check whether your cash can cover the months ahead. Enter starting cash, initial spend, monthly income and costs to see a 12-month forecast and any immediate funding gap.
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Cash Runway Planner
Forecast cash and spot funding gaps using your assumptions.
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- - Enter opening cash (use 0 if none).
- - Enter monthly revenue (use 0 if none).
- - Enter fixed costs (use 0 if none).
- - Enter variable cost rate (use 0 if none).
- - Enter tax reserve rate (use 0 if none).
- - Enter one off spend (use 0 if none).
Constant-assumption forecast: income and costs repeat monthly. The reserve is a planning allowance, not a tax calculation. Month-end balances do not model payment timing within each month.
Not sure where to start? Plan the business basics
Business-Ready start
Get the practical sales basics in place before you pay for more software.
Choose where the business is now, then use the smallest free route that gets it ready to quote, sell, be found, or follow up.
Selected route
Get Ready
- 1. Run the scorecard
- 2. Fix website and profile gaps
- 3. Save a launch-ready action list
Free first. The optional Launch Admin Pack is only for one-off help after the tool output is useful.
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How this tool works
- Opening cash is starting cash minus one-off setup spend. An opening shortfall is shown separately from later month-end depletion.
- The forecast holds monthly income and costs constant for 12 months. It does not model late payments or seasonal changes.
- Enter expected cash received, rather than counting unpaid invoices as available money. Blank fields still need your input.
- A positive month-end balance does not mean you can meet every payment that falls due during that month.
Worked example: £3,000 starting cash minus £500 initial spend gives £2,500 opening cash. £1,000 monthly income and £1,500 monthly costs reduce cash by £500 a month; it reaches £0 at the end of month five.
Review confirmed receipts and export your recordsNext steps open in a new tab so your current draft stays here. Working inputs are not transferred automatically. Copy the details you need to continue.
Use this when
- You need to understand how many months of runway you have.
- You are deciding whether a new subscription, tool, or campaign is affordable.
- You want a quick founder-level view before making a more detailed forecast.
What you get
- Opening cash after initial spend, an immediate shortfall if you begin below zero, and a month-by-month cash forecast.
- Plain-English prompts to think about break-even and cash pressure.
- A useful early warning signal for whether setup spending is getting ahead of sales.
Common questions
What is cash runway?
Cash runway is a rough estimate of how long a business can keep operating before current cash and reserves are used up.
Why include this in a no-subscription toolkit?
New businesses often sign up for tools before sales are proven. A simple runway view helps keep early spending proportionate.
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