Currency Exchange Calculator App

Free Code HTML ~213 words · You get a single-file page you can open in a browser Upvote 0 0 views

Prompt

Role
You are a senior front-end engineer who builds polished, accessible single-file pages.

Task
Develop a comprehensive currency converter using HTML5, CSS3, JavaScript and a reliable Exchange Rate API. Create a clean, intuitive interface with prominent input fields and currency selectors. Implement real-time exchange rates with timestamp indicators showing data freshness. Support 170+ global currencies including crypto with appropriate symbols and formatting. Maintain a conversion history log with timestamps and rate information. Allow users to bookmark favorite currency pairs for quick access. Generate interactive historical rate charts with customizable date ranges. Implement offline functionality using cached exchange rates with clear staleness indicators. Add a built-in calculator for complex conversions and arithmetic operations. Create rate alerts for target exchange rates with optional notifications. Include side-by-side comparison of different provider rates when available. Support printing and exporting conversion results in multiple formats (PDF, CSV, JSON).

Context to use: [your details]

Provide values for: your details

Requirements
• Write complete, runnable code with sensible names
• Make the layout work on a phone and a laptop
• Explain assumptions before the code

Output Format
Complete single-file HTML in one code block, then a short note on how to run it

Refocus
Deliver a complete response that directly addresses the task above.

### Role
You are a senior front-end engineer who builds polished, accessible single-file pages.

### Task
Develop a comprehensive currency converter using HTML5, CSS3, JavaScript and a reliable Exchange Rate API. Create a clean, intuitive interface with prominent input fields and currency selectors. Implement real-time exchange rates with timestamp indicators showing data freshness. Support 170+ global currencies including crypto with appropriate symbols and formatting. Maintain a conversion history log with timestamps and rate information. Allow users to bookmark favorite currency pairs for quick access. Generate interactive historical rate charts with customizable date ranges. Implement offline functionality using cached exchange rates with clear staleness indicators. Add a built-in calculator for complex conversions and arithmetic operations. Create rate alerts for target exchange rates with optional notifications. Include side-by-side comparison of different provider rates when available. Support printing and exporting conversion results in multiple formats (PDF, CSV, JSON).

Context to use: [your details]

*Provide values for: `your details`*

### Requirements
- Write complete, runnable code with sensible names
- Make the layout work on a phone and a laptop
- Explain assumptions before the code

### Output Format
Complete single-file HTML in one code block, then a short note on how to run it

### Refocus
Deliver a complete response that directly addresses the task above.

Fill any blanks first. Open in sends the filled version. Results vary by model.

RTF

Rewritten with RTF

Same goal, restructured into a framework with named slots. The original is still above.

Role
You are a senior front-end engineer who builds polished, accessible single-file pages.

Task
Develop a comprehensive currency converter using HTML5, CSS3, JavaScript and a reliable Exchange Rate API.

Format
Complete single-file HTML in one code block, then a short note on how to run it

How RTF works