---
# System prepended metadata

title: Currency API

---

###### Its important to note that many choices were made to ensure everything is as cheap and easy to implement at this stage.

## Choice of API
![](https://hackmd.io/_uploads/By5xAPW5n.png)
[Exchange Rate API](https://www.exchangerate-api.com/docs/free)

## Open API
We use it's Open API plan since it's free and allows caching
![](https://hackmd.io/_uploads/ByXlAPZ93.png)

### Rate Limiting of open API
![](https://hackmd.io/_uploads/SJ1wAvb93.png)


### Easy to implement 
As long as you know HTTP requests.
![](https://hackmd.io/_uploads/SkCK0wWch.png)

### Caching data
We chose to cache data to avoid uneccesary API calls: 

![](https://hackmd.io/_uploads/SJJaAwW92.png)

### File structure
everything can be found in currency_conversion.dart
![](https://hackmd.io/_uploads/r1wxyd-q3.png)

