Startup Cost Calculator

Most "how much do I need to start a business" answers are rules of thumb — six months of expenses, or a flat percentage of revenue. This startup cost calculator builds the number from your own numbers instead. You list every one-time cost (equipment, licenses, initial inventory, a website build, a deposit on a lease) and every monthly recurring cost (rent, salaries, software subscriptions, insurance) as separate line items, set how many months of runway you want to survive without new revenue, and add a contingency percentage on top as a buffer.

The math is straightforward but the value is in doing it honestly, row by row. totalOneTime is the sum of every one-time item; monthlyBurn is the sum of every recurring item. The base capital needed is totalOneTime plus monthlyBurn multiplied by your runway in months — in other words, everything you spend once, plus everything you spend every month, stretched across the whole survival window. The contingency percentage is then applied on top of that base total, because the plans that fail are usually the ones with no room for a permit that costs more than expected or a launch that slips by two months.

The result panel breaks the total into its one-time and recurring shares, so you can see at a glance whether your capital need is dominated by upfront spending or by the accumulating monthly burn — the second is the more dangerous one, because it keeps consuming cash for as long as the business is unprofitable. Alongside that sits a genuinely useful readout: how many additional months of runway another 1,000 in funding would buy you at your current burn rate. That single number reframes a fundraising or savings target from an abstract lump sum into a concrete amount of extra survival time.

Everything runs locally in your browser — no sign-up, no server, and it works in any currency since the numbers are unitless. Add and remove cost rows freely as your plan evolves, recompute whenever a supplier quote or a rent figure changes, and treat the contingency percentage as a dial: raise it for a business with more regulatory or supply-chain uncertainty, lower it once you have real vendor quotes instead of estimates.