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Cash Runway CalculatorDesign concept

Cash Runway Calculator

Opening cash, monthly operating cash in/out and optional dated one-time expenses. Calculate cumulative balances month by month; distinguish constant-burn estimate from detailed cash forecast. No investment advice.

A visual concept with a complete implementation prompt. Use the prompt to build the working app.

Published by build.host
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406 words · Complete build specification

BUILD SPECIFICATIONDownload .md

ONE-PAGE TOOL: Cash Runway Calculator Build one complete, working single-page utility for a US small business. No signup, dashboard, admin console, account setup or multi-page app. The page follows input → live preview/result → copy, print or download. Optional browser-only draft storage must be clearly labeled with Clear all.

INPUTS, CALCULATIONS AND OUTPUT Opening cash, monthly operating cash in/out and optional dated one-time expenses. Calculate cumulative balances month by month; distinguish constant-burn estimate from detailed cash forecast. No investment advice.

ACCEPTANCE EXAMPLE 90000 cash with 25000 out and 10000 in per month gives 15000 net burn and six months. Nonpositive burn displays cash not declining under this scenario, not a fabricated depletion date.

US LOCALE Use USD, en-US thousands separators, two-decimal currency outputs, American English and US names (Emily Carter, Jessica Miller, Maple Goods, Oak Supply Co.). Use US addresses, ZIP strings, US Letter printing, inches and pounds when relevant. Dates must be unambiguous; numeric dates use MM/DD/YYYY. All samples are fictional and available through Load example, never mixed into user data. Any tax rates are user-configured examples, not a national rate.

IMPLEMENTATION Use decimal-safe money arithmetic and explicit rounding at the displayed/exported precision. Validate inputs inline, show useful empty/error states, and preserve edits during recalculation. Never fabricate OCR, payment, email, postage, cloud save or export success. Process files locally where possible. No network upload of user files without an explicit user action and destination. Actual downloads must open and contain the displayed totals. If PDF export is implemented through browser print, label it Print / Save as PDF. Do not add unnecessary backend dependencies.

DESIGN Follow the supplied preview composition and palette; translate tiny gallery text to accessible 16px body and labeled controls. Responsive one-page layout, 44px touch targets, keyboard focus, readable contrast, no horizontal overflow. Keep input and output together on desktop; stack them in workflow order on mobile. Use actual product uploads when requested; no stock photos of unrelated people or regional factory imagery.

VERIFY Test the numeric example above, zero/blank/negative inputs, reset, repeated export, keyboard operation and a 390px mobile viewport. Ensure printed pages have no navigation, clipped rows or missing totals. Deliver the working tool and explain only real required integrations.

VISUAL REFERENCE Brand: RESERVE. Headline: Make time for what’s next.. Composition: timeline. Palette: green. Primary action: Export cash forecast. Preview inputs: Available cash: $90,000; Monthly cash out: $25,000; Monthly cash in: $10,000. Preview result: 6 months — ESTIMATED CASH RUNWAY.