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Build a marketing ROI calculator

Sharable URL state is the secret — people share calculator results, not calculators.

by @whitney · recommended tool Claude Code · 0 unlocks

EXAMPLES · WHAT THIS PROMPT PRODUCES

Sample output

**Built: interactive ROI calculator for an SEO agency retainer**

Delivered as a single `roi-calculator.html` — open it in any browser, no build step.

**Inputs (sliders, with live labels):**
- Monthly organic visitors (range 500–100,000)
- Conversion rate (0.5%–8%)
- Average order value ($10–$2,000)
- Expected traffic lift from SEO (10%–150%)
- Monthly retainer cost ($1,500–$15,000)

**Outputs (update live as you drag):**
- New monthly visitors
- Additional revenue/month
- Net ROI ($ and %)
- Payback period (months)
- 12-month projected return

**Logic:** added revenue = (visitors × lift%) × conversion × AOV; ROI% = (added annual revenue − annual retainer) ÷ annual retainer.

**UX details shipped:**
- Sliders + instant output cards, color-coded (green when ROI positive, amber when break-even).
- **Shareable URL** — every slider writes to query params, so `?visitors=12000&cvr=2.5&aov=85&lift=60&cost=4000` reproduces the exact result. This is the growth lever: a prospect drags it to their numbers, sees a 4.2x return, and shares the link with their CFO.
- A sticky **"Talk to our team"** CTA that passes the current inputs along.

Fully responsive, self-contained, no dependencies.

PRICE HISTORY0 cr · current

PROMPT TEMPLATE · v1.0.0

Build an interactive ROI calculator for <SERVICE>.
Inputs: <INPUTS_WITH_RANGES>. Outputs: <OUTPUTS + UNITS>.
Logic: <FORMULA or assumptions>.
UX: sliders + live output, shareable URL (state in query params), "Talk to sales" CTA.
Tech: single HTML file.