Build a clean, fast currency converter supporting 30+ world currencies. Features an instant swap button, country flag icons, and hardcoded exchange rates that your AI agent can update periodically with a simple follow-up prompt.
Build Prompt
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Build a single-page currency converter as a static HTML/CSS/JS site. Page background #0f0f17 with a centered card (max-width 560px) using #12121a background, 1px solid #2a2a3a border, and 20px border-radius. Design mobile-first.
At the top, display "Currency Converter" heading in white and a subtitle "Fast, offline-ready conversions" in #8888a0. Show a small "Rates updated: [date]" badge in #6a6a80 text below the subtitle.
The converter layout has two currency rows stacked vertically with a swap button between them. Each row contains: a currency dropdown (searchable, with the currency code and full name, e.g., "USD - US Dollar") on the left (40% width) and an amount input on the right (60% width). Style dropdowns with #1a1a2a background, #2a2a3a border, white text, and a custom chevron icon. Style amount inputs with large 24px font, #1a1a2a background, right-aligned text. The top input is editable; the bottom shows the converted result (also editable for reverse conversion — both inputs should update each other in real-time).
Between the two rows, place a circular swap button (48px diameter, #1a1a2a background, #3b82f6 icon) centered with horizontal lines extending to the edges. Clicking it swaps the from/to currencies with a smooth 180-degree rotation animation on the button icon.
Include a conversion rate display between the rows showing "1 USD = X EUR" in #8888a0 text, updating dynamically when currencies change.
Below the main converter, add a "Popular Conversions" quick-access grid — 6 buttons in a 3x2 grid showing common pairs: USD/EUR, USD/GBP, USD/JPY, EUR/GBP, USD/CAD, USD/AUD. Clicking a pair auto-selects those currencies. Style as small pill buttons with #1a1a2a background and #2a2a3a border.
Below that, add a "Conversion Table" section that shows the selected base currency converted to the 10 most popular currencies in a compact table. Columns: Currency, Code, Rate, Converted Amount. Style with alternating row backgrounds (#12121a and #16161e).
Hardcode exchange rates for at least 30 currencies as a JavaScript object at the top of the script (all rates relative to USD as base): USD, EUR, GBP, JPY, CAD, AUD, CHF, CNY, INR, MXN, BRL, KRW, SGD, HKD, NOK, SEK, DKK, NZD, ZAR, THB, PHP, IDR, MYR, TWD, PLN, TRY, RUB, AED, SAR, COP. Use realistic current exchange rates. Include a comment marking the rates object clearly so it is easy to find and update.
Add a search/filter feature in the currency dropdowns that filters as the user types. The entire layout should be responsive and work beautifully on mobile. All conversions update in real-time with no button click needed.
Read the guide at https://accessagent.ai/api/guide and follow it to deploy the site to AccessAgent.ai. My email is [your@email.com].
Update Prompt
Use this prompt to refresh exchange rates
Update the exchange rates in the currency converter. Find the JavaScript object containing the hardcoded exchange rates (all relative to USD as base currency) and update every rate to the latest values as of today. Also update the "Rates updated" date string shown in the UI to today's date. Do not change any other code, styling, or functionality — only update the rate values and the displayed date.
After updating, redeploy the site following the guide at https://accessagent.ai/api/guide. My email is [your@email.com].
Make It Yours
Cryptocurrency Support
Add BTC, ETH, SOL, and other major cryptocurrencies to the currency list with their current USD exchange rates.
Historical Rate Chart
Show a 30-day rate history chart for the selected pair using hardcoded historical data that the agent can update weekly.
Travel Budget Mode
Enter a budget in your home currency and see how much you get in the destination currency with common expense breakdowns.
Rate Alerts
Let users set a target rate and store it in localStorage — show a banner when the hardcoded rate crosses their target after an update.
Fee Calculator
Add a toggle to include typical bank/ATM conversion fees (2-3%) to show the real amount received after fees.
Multi-Currency View
Show a single amount converted to 5 user-selected currencies at once for comparing rates across destinations.
SEO Tips
Target "currency converter" and "exchange rate calculator" as primary keywords — "currency converter" gets 5M+ monthly searches globally.
Create individual landing pages for top pairs: "USD to EUR converter," "USD to GBP converter" — each gets 100K+ monthly searches as long-tail queries.
Add structured data using ExchangeRateSpecification schema for each currency pair to appear in Google's currency converter rich results.
Include a "Currency Guide" section with brief descriptions of each currency (name, symbol, country, central bank) for informational search traffic.
Write companion content: "Best Time to Exchange USD to EUR" and "How Exchange Rates Work" to build topical authority.
Monetization Ideas
Add affiliate links to forex transfer services (Wise, OFX, Remitly) with a "Send Money Abroad" CTA — transfer affiliates pay $10-30 per referral.
Offer a premium "Rate History" mode for $2.99 with 90-day charts and trend analysis for each currency pair.
Place travel insurance affiliate ads (World Nomads, SafetyWing) targeted at users converting to travel destination currencies.
Create a travel money card comparison section featuring Revolut, Wise, and N26 — earn per signup or card activation.
Sell an embeddable widget to travel blogs and agencies for $19 one-time with their branding — they embed it on their booking pages.