b2KIT

Startup Cost Calculator

Estimate total startup costs by category (legal, equipment, marketing, inventory) with funding needs and cash runway projection.

Tested tool guide Tested browser tools Checked August 16, 2026

What Startup Cost Calculator does, with a checked example

A startup cost estimate is only half the story. The total says what launch costs, but the runway figure says when the money runs out, and founders are routinely surprised how early that is once salaries, rent, and insurance are counted as monthly burn. This tool collects planned costs by category - legal, equipment, marketing, inventory, plus operating expenses - sums them into a funding need, and divides cash by monthly burn to project how many months the funding lasts.

Worked example

A concrete input and expected output from the current implementation.

Input

Legal: $2,500 / Equipment: $15,000 / Marketing: $4,500 / Inventory: $9,000 / Other: $4,000 / Monthly operating costs: $7,000

Expected output

Total startup cost: $35,000. Funding need: $35,000. Cash runway: 5.0 months at the stated $7,000 monthly burn.

The tool sums the five cost categories to $35,000 (2,500 + 15,000 + 4,500 + 9,000 + 4,000), which is also the funding need when the plan is fully funded up front. Runway divides that cash by the monthly burn: 35,000 / 7,000 = 5 months, so the money is exhausted at the start of month six.

How the result is produced

1

Category totals

Costs are entered under named categories - legal, equipment, marketing, inventory, and operating expenses - and the tool sums each category, then all categories, into a single startup cost total. The funding-need result follows directly: the cash required to cover those items before revenue arrives. The tool does not add anything you do not enter, so an unlisted cost is simply absent from every result.

2

Runway division

Runway is one division: cash available divided by monthly operating costs, giving the number of months the money lasts. With $35,000 funded and $7,000 of monthly costs, the result is 5 months - the cash is exhausted at the start of month six. Because of the division, a $500 error in monthly costs moves the result by roughly a third to half a month, so the monthly figure deserves the most scrutiny.

Good uses

  • A would-be founder wants to know whether savings plus a small loan can cover launch. They enter the planned purchases and monthly costs and compare the funding need against what they can actually raise before leaving a job.
  • Comparing two versions of the same idea - a home-based service versus a rented storefront - to see which one survives longer, since the scenarios differ mainly in equipment and rent and the runway figure makes the difference concrete.
  • Preparing a funding request for a bank or investor: the category breakdown becomes the spending plan attached to the application, showing what the money buys (legal, equipment, marketing, inventory) and how long it lasts.

Limits and checks

  • The total is only as complete as the entries. Recurring items - annual licenses, insurance premiums, software subscriptions - are the most commonly skipped costs, and since the tool totals exactly what is typed, an omitted item appears nowhere in the result.
  • Category boundaries overlap: a website could sit under marketing or equipment, an accountant under legal or operating costs, so the same spending can be counted twice. The total stays meaningful only if categories are kept disjoint.
  • Runway assumes a constant burn and no revenue. Early sales stretch it beyond what is shown; hiring, rent increases, or supplier price rises shorten it. Treat the figure as the worst-case deadline for revenue, not a forecast.

Common questions

My runway comes out to four months. Is that a sign I shouldn't start?

Not by itself, but it is short. It means the money runs out early in month five if nothing changes, which leaves little time for the business to find customers before the cash does. The practical response is to extend it - trim the burn or raise more before launch - rather than to treat the number as a verdict on the idea.

Should I include my own salary as a monthly cost?

Yes, and it is the line founders most often leave out. If you draw a salary or living allowance from the business, it is a real cash outflow and belongs in monthly operating costs, alongside any day-one employees. Omitting it flatters the runway by exactly that amount. If you plan to live off savings, exclude it deliberately and note that assumption.

References and verification

The example and behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.

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